switch ports flapping Flapping is normal, it's part of vmware sending from both NICs. 565d. A switch port configured as DTP dynamic desirable mode will actively try to convert the link to a trunk link using Dynamic Trunking Protocol (DTP). I'm keeping you informed as soon I'm testing it. I have deployed a 5230 appliance with 2. --> By default, the ports are Ethernet ports but you can change the port mode to Fibre Channel on the following unified ports: To protect the CPU from continuously updating the CAM table with the same MAC address(es) flapping between interfaces, dynamic MAC address learning is disabled for the entire switch for 3 minutes. This post is a short one, but hopefully still valuable. I’m using MikroTik routers at all of these sites. c6a8) Configured speed auto, actual 1Gbit, configured duplex fdx, actual fdx Both switches are connected via the 2 gigabit ports on each switch - gi1/1 &gi1/2 on each server. For example MAC address ab-bc-cd is coming from the server connected to TOR Stack switch in City B. We have a pair of appliances setup in a VSX cluster. Each of these interfaces are plugged into the same switch and causing mac flapping on the switch. 202 P2p . Cisco Switching/Routing :: 2960 Switch Ports Flapping Feb 4, 2013. Follow the below . I was attaching a headless test device to a 3750G and I couldn’t see the status of the NIC from the tester’s perspective. Figure 3-4 shows how MAC address flapping occurs. This time I didn't get any MAC address flapping errors on the switch but if I pulled out cable A everything continued working. I still have that but it doesn't cause any issues. This feature will monitor the MAC forwarding table and if a MAC address is learned 3 times or more on different ports within 10 seconds MAC flap detection feature will report it to the dashboard as shown in the image below The ErrDisabled state indicates that the switch detected a problem with the port and disabled the port. The only problem was that the switch wasn't connected to anything. The most important benefit of the switch port monitor is that it automatically discovers switches operating at near full capacity. Flapping trunk port Hi, we have a 3750 connected via portchannel trunk to a 6500 switch. Learn why and how ports are automatically disabled/shutdown, how to configure the Catalyst switches for autorecovery from err-disable states and selectively disable Errdisable feature for different reasons. Confirmed the port flapping was a bad connector plug. switch IOM as illustrated in Basic Network Topology, the uplink switch ports must have the same IEEE 802. For my switch this was EEE, Auto Power Down, and Short Reach. Include two or more physical NICs in a team to increase the network capacity of a vSphere Standard Switch or standard port group. 1. Dell EMC VxBlock™ and Vblock™ Systems 740 Administration Guide|30|HTML|en|17300454|U|U|740-administration. Prevents The network adapter flapping was completely solved in my case by disabling the power saving options of the ethernet port associated with the One Link Pro Dock. The trap sent will use the SNMP OID of HBA issues and port flapping on NetApp NDMP appliance can cause SCSI commands to abort. 21d4 in vlan 12 is flapping between port Gi3/0/7 and port Gi3/0/6 Port flapping is a situation in which a physical interface on the switch continually goes up and down, three or more times a second for at least 10 seconds. This causes Flapping on cisco switch, as the same MAC address is seen on SW1 coming from port-1 and Trunk1 Same is happening on SW2, same MAC is seen on interfaces: port-5 and Trunk1 This makes setup unstable, and the two Peplink devices are fighting who will be the master. Go into winbox and turn on the column 'last link down time' in interfaces - this will tell you if indeed the ports are flapping. Some across the same switch and some between different switches. Select a load balancing algorithm to determine how the standard switch distributes the traffic between the physical NICs in a team. Besides, RSTP can provide much faster spanning tree convergence. RSTP. Hello all! I currently have a conondrum between a Cisco router and Cisco switch. Cisco 2960x - Stack port flapping UP / DOWN It is the first time I experience this after installing more than a hundred 2960x switches. Out of the 23. same like "ipereandres" in thread post #23 Basically there is no issue with that. Switch logs show bonded switchports flapping connected to Red Hat Enterprise Linux 6 host Why does the switch report our bond ports are flapping? - Red Hat Customer Portal To start monitoring SNMP, you need to click Add against SNMP interface, specify IP address of device that you will be monitoring or DNS name and a port of your SNMP interface which by default is ‘161‘. 1W does not consider Edge ports in the spanning tree calculations. Bond Mode 4 is useful with the LACP use case, where multiple ports on the switch might be configured to do LACP, while Bond Mode 1 can be used in the other use cases. At other locations, it’s been much worse. Netgear support not very helpful. Our CMM has 4 AP, each AP has 15-30 SM. Port Flapping is just a symptom. Port Gi1/0/23 on our Cisco 2960s keeps flapping that runs to another switch (HP v1910) with client devices connected to the HP switch. 3. Details Open Server Gaia Kernel Version: 2. First: triple check physical cabling it should be certified end-to-end (from PC/VoIP Phone port to Switch port), after that check for looping especially in involved VoIP Phones (I've seen idiots doing silly things on Ethernet Ports of VoIP Phones) then you should check your VLANs Host is flapping between 2 ports on a switch. 13. You can advise the switch it is normal by creating an etherchannel. Listed below are few of the Port flapping; Network inaccessible There is a way to configure the device to have all ports switch together and yet be able to use VLAN filtering on a hardware The virtual switch provided by Hyper-V is compliant with the official 802. c698 (bia cc4e. Each host has its’ 2 pNICs connected to separate physical switches. 6). 168. leclerc. You should, if possible have the "primary" velop directly connected to the router on ethernet port 1, and the "primary" velop ethernet port 2 connected to the first switch; you choice. This article provides a background on the causes of Mac address Flap . I was recently troubleshooting a vPC port channel issue with a pair of Nexus 5500 switches that were trying to implement new port channels to two NetApp controllers. 1. Matt F. flapping between switch and fortigate after this setup, the switch said that there is flapping in the switch port 1/7, so what do i need to change to prevent this looping? < Message edited by FelixTam -- 10/30/2013 8:21:41 AM > L1 switches have very low latency and do not store or manipulate a single bit in the data stream. Could we tell where is the issue by the log below: Nov 20 2015 08:44:22. First make telnet connection with the switch. Cisco switches are packed with in-built security feature against MAC flooding attacks, called as Port Security. In the picture above, the UCS is networked using a pair of UCS 6248UP Fabric Interconnects to a pair of Nexus 5548 UP switches. In another FreeNAS 9. xxxx in vlan 1 is flapping between port Po20 and port Gi0/24 Sep 14 13:48:59. 0000. I installed stacking modules on two 2960x switches in order to stack them. I have also verified that disabling STP on the port that is STP flapping will also eliminate the issue. For some reason my Cisco switch with the flapping goes to : Gi4/10 Desg BLK 4 128. Both physical NICs of this server are connected to Cisco switch on access ports. 6 - R75. cd72. Over the past couple of days I noticed my internet downloads were much slower than before. the goes down again. 0cbb. MAC address flapping may occur on an aggregation switch in specific scenarios, for example, users roam between APs and a PC goes online through different access switches. 0000. Let's take a deeper look. HUAWEI SWITCH S5700 - HOW TO Configuring MAC address anti-flapping More needs? See hints on www. In one case it was a ubiquiti edgeswitch, and in another case it was a netonix ws-6-mini (1. I don't like the prospect of having the Velop "primary" down stream from the router connected via two switches. Conditions: 1. 0P0). Port mirroring Enables traffic on a port or VLAN to be simultaneously sent to a network analyzer for monitoring. I also tried all the recomandations + enable the USB 3. This should be seen in the MAC address table. Additionally, you might want to protect the root ports on the edge switches so that no rogue switch can grab the root. If you have Switch access, you should know about the connected ports of your Server so that you can configure the same LACP port-channel in switch side. The 4048 in my live environment now has nothing connected to it other than a single uplink to the core and has been updated to firmware 9. Troubleshooting flowchart. Lv Adding Switch PORT separately using IP and PROBE Its time to add PORTs in your map so they can appear separately as showed in the title image Go back to your MAP, Right click and ADD new device, Type your switch IP address, and click on Next, Now DO NOT click on Discover, simply click on + sign In PROBE, Select the PORT 9 probe you created earlier Dear All, We are facing a strange problem that the mac-address-table address 02:01:00:00:00:00 is flapping and belonging to more than one machine, because of which the core CPU switch utilization is increasing a lot. In most environments that I worked in we exclude sending this trap from user access ports for that reason and only monitor this on interconnects. pdf|Platform VB 740 Set up VxBlock Systems to use VxBlock Central Configure port flapping for switches Hey all i have 2 switches which are both onnected to a router, and the router is configured with bridging to provide redundancy. 1q standard, which means that it can assign its virtual switch ports to virtual local area networks (VLANs). The common cause is usually related to bad, unsupported, or non-standard cable or Small Form-Factor Pluggable (SFP), or related to other link synchronization issues. 7a1d. pdf|Platform VB 740 Set up VxBlock Systems to use VxBlock Central Configure port flapping for switches We've set our core switch to priority 4 (16384) and the other central switches to 6 (24576). Interface is going into err-disabled even without SFP inserted into the port reported. Symptom: The device that is affected by this software defect might be dealing with interfaces flapping unexpectedly or going into err-disabled. 1 (change the ip as required,) Enter Password to continue. By analyzing the above output, the port that flapped and the time at which the flap occurred can be identified. Mar 9 14:52:19. Switch OS 4. I've not had any issues since I re-seated the plug. 1Q trunks or Link Aggregation (LAGs) configuration. MAC address flapping can cause an increase in the CPU usage on the device. Detection of link flapping will cause the sending of traps and the partitioning of ports as configured. This is to avoid MAC flapping at the physical switches. My assumption is that since the Xbox isn't passing data while flapping, that the switch just shuts the port off completely until data starts flowing. I have a 2960 switch and every then and now the ports are flapping, while i was on console i saw ports going down and coming up when the ping to machine ip addresses timed out the port status on switch was still up no errors collisions seen on sw port. Any experience with Mellanox and FreeNAS in regards to flapping in general? Switches are Dell/Force10 S4048-ON 48 Port SFP+. After doing this the port flapping has stopped completely. 3ad without spending a ton of cash. But if you see items flapping and changing their status constantly, or SNMP Ebay usually has pretty good prices for used Cisco equipment but with gigabit switch prices dropping you can buy a new switch with support for 802. In both cases, disabling STP on the radio port on the far end switch has fixed the issue. I know i can use Active/Standby mode, but my problem is why Microsoft lets to select other algorithms in switch independent mode when it knows it creates big problems. After much digging it turned out that the copper traces for those two SFP+ cages were longer that the traces of all the other ports. It's not between port 5 (eth4) and 6 (eth3). Have a look at your physical switch configuration to ensure it’s configured correctly. 168. We have flapping between these ports. MAC Flapping on a HP Procurve Switch for a Company - posted in Networking: I have a network connectivity issue where both my hardwired and wireless connections are fluctuating. Looking at the porterrorshow on my switchs I saw a lot of loss of sync on the Switchs ports. xxxx in vlan 1 is flapping between port Po20 and port Gi0/24 Sep 14 13:48:43. Flapping port - VMware Technology Network VMTN. MSTP Step 1. 2 with 32 bytes of data: Request timed out. ipmax. ). g. To clarify, in the logs the ports that are flapping are the 16 ports that connect 3 switches to my root switch and they are only alerting from the perspective of the other 3 switches, the root switch sees no issues with the his end of those 16 connections (its own 16 ports). I spent lots of time trying to figure out what that switch controlled. Adding Switch PORT separately using IP and PROBE Its time to add PORTs in your map so they can appear separately as showed in the title image Go back to your MAP, Right click and ADD new device, Type your switch IP address, and click on Next, Now DO NOT click on Discover, simply click on + sign In PROBE, Select the PORT 9 probe you created earlier Check the client driver and firmware. Determine the interface where the MAC address flapping occurs. The reason (or reasons) behind a Port Flapping can be tricky to diagnose. Use the command 'show spanning-tree interface' to check the interface state, verify that the ports are in steady state and not flapping between states (ie Forwarding, Blocking or listening). Hi, I'm using RB2011UAS, RouterOS 6. Event logging and alerts A port can become degraded because of a soft failure event, such as link flapping (links bouncing quickly between up and down) or network partitioning: Network ports in the cluster IPspace are marked as degraded when they experience link flapping or loss of layer 2 (L2) reachability to other network ports in the broadcast domain. When a flapping port is part of a trunk, a trap will be sent for that port but the port will not be partitioned. The port flapping frequency is not constant. 7715 in vlan 3 is flapping between port Gi0/2 and port Gi0/5 Jul 22 12:18:54. Use bulk requests is turned on by default. I got involved when my storage friend sent me an email one evening asking me to check the port channel for one interface that was not wanting to participate in the port channel STP switch port states: Blocking - A port that would cause a switching loop, no user data is sent or received but it may go into forwarding mode if the other links in use were to fail and the spanning tree algorithm determines the port may transition to the forwarding state. The ranges containa a name, a range and the configuration statements which is common to all the similar interfaces. Link flap can be caused by end station reboots, power-saving features, incorrect duplex configuration or marginal connections and signal integrity issues on the link. Symptoms. %SW_MATM-4-MACFLAP_NOTIF: Host 8cc8. After many hours of So i Have a stack of 4 Dell N2048P Switches that im having problems with the Ports flapping or going up and down speradically (at least in 5 minute intervals). Here are the steps to resolve this issue. Plan to fully rewire and remove the plug and socket sometime soon. 302 CST: %SW_MATM-4-MACFLAP_NOTIF: Host 0cc4. BEST PRACTICE Cohesity supports Bond Modes 1 (active-backup, the default) and 4 (802. com Re: MAC flapping between port It is very normal on the switch to display this mac flapping message if APs are connected to the switch port. * Port 3 connects to a PC or other device. Favorite Answer. If I swapped them and pulled out B everything would drop. I bought a switch on amazon with 3 usb ports and 1 RJ45. 1 decade ago. 11(2. If the port connected to other port is capable to form a trunk, a trunk link will be formed. 991c. com hello, I am getting this flapping messages in switch but i cant find the mac address on any of the ESXi server. This is actually a known cause and effect and I would even say that is the expected behavior. In its most basic form, port security ties a given MAC address to a port by not allowing any other MAC address than the preconfigured one to show up on a secured port. 0011 in vlan 1001 is flapping between port Gi0/23 and port Gi0/15 Yes, the Velop does work with switches. 1141 in vlan 60 is flapping between port Po1 and port Po3 Port switch is flapping due to similar MAC address 02:00:00 of multiple different cluster members in the same network segment. Lv 4. Each of the FWs has an interface on VLAN 123 within the same subnet, 10. The RB3011 router from MikroTik can sometimes have issues with Ethernet ports flapping, which can sometimes be traced back to using different link speeds on different ports on the one switch chip. All, I am wondering what the best way to mitigate MAC Flapping on a cisco switch. conf configuration from duid to clientid and then reboot. Community. Cause Cluster correction packets are being forwarded between the cluster members with a fixed source MAC address: 02:00:00:00:00:mem_id Dell EMC VxBlock™ and Vblock™ Systems 740 Administration Guide|30|HTML|en|17300454|U|U|740-administration. s flapping between port Po1 and port Gi1/2 How to stop flapping messages from a Cisco switch from being logged to the Orion syslog server bbeachy2001 over 3 years ago I have about 120 AP's at our high school, and people are roaming around all the time, so I'm getting tens of thousands of flapping messages being logged. IPMAX is the ideal partner for companies seeking quality in products and services. Another good option is the Netgear GS748TNA 48 port switch. even i can not find any VM with the mac given mac address in physical switch. It used to be connected with a 50m (not 30m as previously stated) CAT 5e cable - what I did not mention is that it is an Access point having a Power Injector inbetween. And the "port-isolate enable" command is used to implement Layer 2 isolation between interfaces. Set it and forget it, energy-efficient switches are built like tanks and last for decades. * Port 2 is an internal 10/100 interface that carries the phone traffic. HUAWEI SWITCH S5700 - HOW TO Configuring MAC address anti-flapping IPMAX is a Huawei Partner in Italy. aaaa in vlan A is flapping between port 0/1 and port 0/2. On my C5210 Extreme Wireless Controller, I have a lag2 which consists of esa2 and esa3. • When there is a loop, the switch can learn the same MAC address through multiple ports connected to other switches. Check the ports on the SAN switch for FC, Link State Errors. The priority of the edge switches stays at 8 (32768), so they won't ever become root. The internal hardware architecture of the L1 switch allows the L1 switch to duplicate any incoming data to any number of output ports at full wire speed without dropping a single bit. Relevance. what is port flapping? Answer Save. Page 18: Port Side Of The 8/80 San Switch Port side of the 8/80 SAN Switch The port side of the 8/80 SAN Switch includes the system status LED, console port, Ethernet port and LEDs, USB port, and FC ports with corresponding port status LEDs. Let’s see what happens when we try a ping: C:>Documents and Settings>H1> ping 192. once i shut down one port (port 4) the flapping stop. The ports on the physical switches are all within the same vlan (the storage vlan of course). Ports A1 and A2 have been previously configured for a static LACP trunk. 2 U2 there's a bug fix for dhclient concerning flapping but this Link is flapping . So reading some threads here I saw that one of the recommendations was to change the /etc/dhcpd. × However, I re-tested last night using ports 3,4 instead of my production ports 1,2. The port LED is set to the orange color and, when you issue the show interfaces command, the port status shows as Errdisabled. If the TC (Send) statistics of many ports increase, check NMS events and logs on the switch to analyze the root cause of STP topology changes and determine which port flaps. 2 Pinging 192. I have a cisco layer 3 switch and for some reason the uplink which is a fiber keeps going down. Thank you for watching and we hope you have learned something, if you did please feel fr Device Port flapping Device can do 1000/FD and is connected with a CAT 5e cable. 071: %SW_MATM-4- Hey all i have 2 switches which are both onnected to a router, and the router is configured with bridging to provide redundancy. 0. The interface which is configured as DTP dynamic desirable mode will generate DTP messages on the interface. As soon as there is traffic We’re actually having a similar issue also b5c same issue flapping port, whats funny is when it autonegotiated to 1000mbit clients traffic over the ethernet+rf was showing sub 100mbit like 20mbit, and the port was flapping… we forced the port to 100mbit and somehow that seems to mostly fix the issue the speeds getting 100mbit now but still i see port flapping, also we need more than Link flap is a condition where a communications link alternates between up and down states. In the above example, the switch's current time is verified. Setting it to 100/FD. config. Try other port, other switch, other cable, other IP addres, problem stays. 40 Follows some of the logs of this problem. same like "ipereandres" in thread post #23 Basically there is no issue with that. When i configure the Load-Balancing method of the trunks to "IP-Hash" the virtual hosts are flapping in between the portchannel-groups: 21-07-2017 09:00:45 Warning (4) SW_MATM-4-MACFLAP_NOTIF Host 0050. As an aggregate route will not be withdrawn as long as at least one of the aggregated subnets is still valid, a flapping route that is part of an aggregate will not disturb the routers that receive the aggregate. The topology is this: One of our switch Cisco 3550 has the Uplink = Gi1/0, CMM = Fa0/2. Run show log on the switch where the port keeps flapping. During the configuration of FibreTransport media server, I had several issues with the link between SAN Switch (Brocade 16Gb FABOS 7. g. My LAN is as follows; Sky BB -> Mikrotik CCR1009 -> port 5 sw 251 port 1 -> port 1 sw 252 port 3 -> Edimax Pro Wifi 1750 -> old 100Mb netgear sw -> Q mini. Interface ranges represent similar type of interfaces with common configurations that are grouped together. 18 Server OS Log on physical switch shows that Check Point MAC Address 0000. 254: %SW_MATM-4-MACFLAP_NOTIF: Host 0000. I also see on my non-flapping Cisco switch that the SRX is not seen as an EDGE port which is what I would have thought it would have appeared as. There is no stable connection, and devices constantly disconnect/reconnect at 10M/100M/1000M. telnet 10. Link flap is a situation in which a physical interface on the switch continually goes up and down, three or more times a second for duration of at least 10 seconds. 243f. 6. 0. This is the normal state for a port. I don't do that because I want my printers to be port portable. cisco. Often though, a single switch interface can support multiple speeds. As a matter of a fact, 16 ports will be over kill but he MAC Flapping : Updates for N5k_N7k switches awareness Host 000b. On my Cisco side, I am seeing MAC flapping between the two lag ports . View solution in original post Something was mentioned about a port on the 4507 "flapping". If the TC (Send) statistics of only one port increase, this port flaps. The RB3011 contains two switch chips, both being the QCA8337 switch chip. (For more on the Active parameter, see LACP port status data. The RB3011 router from MikroTik can sometimes have issues with Ethernet ports flapping, which can sometimes be traced back to using different link speeds on different ports on the one switch chip. . I know i can use Active/Standby mode, but my problem is why Microsoft lets to select other algorithms in switch independent mode when it knows it creates big problems. An IP phone contains an integrated three-port 10/100 switch. . 0 port in the BIOS but it doesn't work. In the picture above, the UCS is networked using a pair of UCS 6248UP Fabric Interconnects to a pair of Nexus 5548 UP switches. 8. ” This is where a link, typically 10G SFP+ on the front or back faceplate, will go down then back up in a very brief period of time. 3e16 in vlan 100 is flapping between port Po20 and port Gi5/0/25 MAC-ADDRESS flapping, please help Hi all I have an issue with a MAC-ADDRESS flapping in my network on one of the routers that links two of our sites. You can easily reclaim unused ports to facilitate intelligent capacity planning and purchase decisions. All these issues will affect switch performance and must be corrected. it 7. Logs on Cisco Switch *Oct 20 11:48:26. Also, the network connectivity, if established, would be very inconsistent. Port flapping does not cause any topology change events on Edge ports since 802. switch 2-20 ports, ports on rear - (MRP), automatic port shutdown (link flapping) Security Port Security (IP und MAC) with multiple addresses(50 MACs per port When you configure a NIC Team with switch independent mode and either address hash or dynamic load distribution, the team uses the media access control (MAC) address of the primary NIC Team member on outbound traffic. These are filled with fiber SFP's which connect to a Cisco C3750 (ports 51, and 51 on a 48 port switch). That is: In the case of a loop (all cables are plugged in) one port of the switch should be in blocked (BLK) mode while the other should still forward (FWD) any traffic. 9416 in _LOGICALINTERFACE_ is flapping between port _INTERFACESHORT_ and port ports. SNMP interface. Port Security is a feature of Cisco Switches, which give protection against MAC flooding attacks. 2 U1 with Mellanox ConnectX 3 (2x10 gigabit) and LACP has run for 6 months without issue, recently traffic has increased a bit (from 5-10 megabit to 60-100 megabit avg), and flapping now occurs. 3 Answers. Interface keeps flapping on POE switch. So one crash cart and a bit of port-swapping later, I found the problem. VMs are connected to a port on the Hyper-V Virtual Switch. vmware. Joined Apr 15, 2014 · 5 A port can become degraded because of a soft failure event, such as link flapping (links bouncing quickly between up and down) or network partitioning: Network ports in the cluster IPspace are marked as degraded when they experience link flapping or loss of layer 2 (L2) reachability to other network ports in the broadcast domain. A trunk port is a specific type of port on a network switch that allows data to flow across a network node for multiple virtual local area networks or VLANs. The switch port monitor provides data on network switches by port in use, CPU load, memory used, etc. I investigated further and discovered my LAN connection was working at 100Base-T whereas before it had been a 1000Base-T. If anyone has worked with Cisco stacks, you know how long it takes the entire stack to reload and elect a new master. Many low cost managed switches also disable NWay when hard setting the speed leading to FDX and HDX problems. Figure 1-1 STP Function. The primary NIC Team member is a network adapter selected by the operating system from the initial set of team members. Anyway, never had a reply concerning the spanning tree mystery. So when connecting two RJ45 port Gigabit switches, there is a simple and straightforward way: inserting a standard Ethernet cable (Cat5/5e/6/6a) directly to connect these two switches. See also. The other 8 times it reloaded without any port flapping. MAC Flap Detection MAC flap detection feature is enabled by default in Meraki switches. 1q VLAN-tagged packets to their proper virtual LB1 (LAN) – (port-1)-SW1 (Trunk1) == (Trunk1)SW2-(port-5)–(LAN)LB2. I wound up going with the many recommendations of the HP 1810-24g. I have a Cisco 2911, and a Cisco 3650-X that I would like to configure link aggregation between. A flapping port can cause network instability and disruption as L2/L3 protocols are constantly forced to re-converge and rebuild the topology with every port status change. You might need to identify when port flapping happens on your Cisco devices when doing the following: If I've a lot of Switches and they all report port flapping all around (on different ports) then I would do a deeper diagnostic than a copy&paste (of just one port's log of a unkown Switch), just to provide a better description of what is really going on on the entire net. Note: A switch administrator might refer the static port channel group as LACP, but a 'static' multimode ifgrp or port channel group does not use the LACP protocol, and the two terms cannot Our log system shows there are port flapping in one of our switches. For example, a Gigabit Ethernet interface is often backwards-compatible with original and Fast Ethernet, and is referred to as a 10/100/1000 interface. This post is a short one, but hopefully still valuable. vidiya · Registered. In addition, ensure that coverage is good so that the client does not roam often. Each 6248 has two links to each 5548. 157 EDT: %SW_MATM-4-MACFLAP_NOTIF: Host 9c8e Switches with 10 GE ports: 10-GE ports operating at 10 Gbps. (see posts n this thread around 05/20/14) I still have some problems with flapping on some other connected devices most probably the USB ports. MAC address flapping does not occur frequently on a network unless a network loop occurs. We've set our core switch to priority 4 (16384) and the other central switches to 6 (24576). I spent 30 minutes troubleshooting a flapping switch port in the lab this week. 1. 714 EDT: %SW_MATM-4-MACFLAP_NOTIF: Host 9c8e. 168. When it happens, I have to connect it to other port before it will come up. 3. I have not seen 100FDX ports drop to 100HDX to save power and even if they did, they can do that without flapping the link. I don't like the prospect of having the Velop "primary" down stream from the router connected via two switches. So I've tried that but since Many Thanks for al your help and advice we have connected the two switches via Fa ports and this has stopped the problem until we get a new switch cable RE: Flapping Stack Link on 3750 JMoore64 (MIS) 21 Jan 09 15:03 Even in some switches when it detect there is a MAC Flapping, STP tries to disable one port. However, I have not configured LACP between a switch and a router. 243f. it Or email us your questions to [email protected] Note ESXi does not support LACP, so you can only run "channel-group 1 mode on". UCS flapping port channel. 3ad, aka LACP). After adding the line switchport nonegotiate to the port groups from the Core down to SW1 & SW2 then the flapping stopped occurring. Hi Using FreeNAS 11. The port is UP, but i can't ping the equipment. Protocol flapping Symptom. At some locations, we’ve had very little trouble with this. i changed port on Cisco switch from port1 to port2 connected to RB3011UiAS-RM and i changed port on RB3011UiAS-RM from ether4 to ether5 connected to cisco switch, both with no success. I have 2 1GB pNICs dedicated to this on each host. I am then creating an uplink group for the storage VDS and adding all four of the pNICs and I had a 1984 BMW 524e that had a light switch and a little wheel that adjusted the brightness of the light controlled by the switch. That could be an indication of a serious problem (like a loop) and the switch is letting you know about it. 672b in vlan Y is flapping between port Gi1/0/3 and port Po3 To check the mode setting for a port on the switch, use either the Port Status screen in the menu interface or show interfaces brief in the CLI (see Viewing port status and configuration (CLI)). The 5548 is configured with virtual port channels, so each VPC represents one 6248. If the use of load balancing is purely for redundancy, consider using active standby mode (mode=1). You can also set your switch ports to 100. 0/24. vlan is flapping between port and port Gi1/38 > any suggestion ? An access port can be assigned to only one VLAN. I see a port flapping in the log files of all switches: I 11/13/19 12:06:22 00076 ports: port 36 is now on-line I 11/13/19 12:06:17 00077 ports: port 36 is now off-line I 11/13/19 11:06:10 00076 ports: port 36 is now on-line I 11/13/19 11:06:06 00077 ports: port 36 is now off-line I 11/13/19 06:17:31 00076 ports: port 36 is now on-line I 11/13 Route Flapping Route flapping occurs when a router interface alternates rapidly between the up and down states and it can cripple a router with excessive updates and recalculations. switchport trunk {encapsulation { dot1q } Sets the trunk characteristics when the interface is in trunking Technical Tip for Intel x722 10Gb SFP+ NIC port link flapping when connected to Cisco SX550/SX350 switch MAC flapping between port - Cisco Community. Cisco 3560G network switch reports this error: Log Buffer (4096 bytes): 12:18:49. In Basic Network Topology, CMC port1 and the --> Unified ports are the type of ports in nexus switches that allow you to configure ports as Ethernet, native Fibre Channel or Fibre Channel over Ethernet (FCoE) ports. HP Switch> show lacp LACP LACP Trunk Port LACP Admin Oper Port Enabled Group Status Partner Status Key Key ---- ----- ----- ----- ----- ----- ----- ----- Al Active Trkl Up Yes Success 0 250 A2 Active Trkl Up Yes Success 0 250 My ESXi hosts are connected to two switches as described in figure 1. 1. 1. Turned out that it was only for European marketed cars. One B5c at one site has Cisco Switching/Routing :: 2960 Switch Ports Flapping Feb 4, 2013. ab18. BGP route damping; Supernet If the switch were to then receive a frame on port 0/2 with a source MAC address of aaaa, there would be clash and the switch would log something like this: 1664321: Nov 14 11:18:16 UTC: %MAC_MOVE-SP-4-NOTIF: Host aaaa. 1q VLAN tags to outbound packets from those switch ports and will properly route inbound 802. 2 release. This prevents disabling of a trunk and loss of connectivity to the switch/stack. We have 3 virtual firewalls setup. V. 1. Juniper difference between disabling a port and deactivating a port. 5688. If the physical switch is not configured for an etherchannel, it’ll start getting confused very quickly as it’ll see the same MAC address sending traffic out of multiple ports resulting in what’s referred to as ‘MAC flapping’. A sample of the MAC FLAP log on the switches is shows below: Mar 2 09:24:42. They are attched to Cisco 2950's. Yes, the Velop does work with switches. Configure failover order to determine how network traffic is rerouted in case of adapter failure. I needed to move these 4 switches to a new rack in a new building, and thought it would be a good time to re-configured them and have a better setup. So one crash cart and a bit of port-swapping later, I found the problem. There are no issues with the hosts, the problem is related to the switch. The current date and time of the switch is 2011-11-22 14:40:37 and the interface has flapped at 2011-11-22 13:29:53. If there is absolutelly nothing in common for the flaping ports/devices then it has to be switch misbehaving. A trunk is a point-to-point link between two switches or between a switch and a router. <port-list> Shows a summary of network traffic handled by the Switch Port flapping by I have a simple switch of 24 ports from ZTE and I have another equipment contected to it in one port. 1x), 802. 3. 3 install no flapping occurs using the same switches, even with very megabit avg, but the NIC is an Intel card (and of course another version of FN). Run the display mac-address flapping command to check all historical records of MAC address flapping on the switch (the following information is used for reference only; the display depends on the device configuration). However, the summarization configuration prevents the RTC route flapping from affecting any other routers. I am very familiar with configuring etherchannel on Cisco switches. Port Security To stop an attacker in his tracks, a mechanism called port security comes to the rescue. Think of the trunk port as a “bundle” of individual branches or capillaries in a telecom network connection. For better understanding of the commands, let us first understand the day to day operational challenges faced in the SAN fabric. Page 19: Nonport Side Of The 8/80 San Switch Port f21 on Cisco SF300-48PP, where is Netbitter connected is flapping, every 10-11min. Even in some switches when it detect there is a MAC Flapping, STP tries to disable one port. I'd also suggest that you downgrade the firmware to a stable version - I had this router running for over a year without problems the firmware update killed it unfortunately, i've been trying the RC's but still no luck. 491: %SW_MATM-4-MACFLAP_NOTIF: Host 0050. Get networks up and running with plug-and-play unmanaged switches. Down and Up port at the same intervals. However now if i have multiple switches on which the same interface is bouncing it would all catch it under 1 hit. The ports, which are dedicated connections, are described as follows: * Port 1 connects to the Catalyst series switch or other device that supports Voice-over-IP (VoIP). Select all Open in new The symptoms were random, but included switches being removed from the stack randomly, PoE drops, and full blown switch crashes with reloads. 1. Four of my servers are experiencing random port flaps on then 10G. For some weeks now, I notice every some minutes flaps on the ports of switch1, ether1 to ether5, about 2-3 secs in duration UCS flapping port channel. Gigabit 16-port Unmanaged Switch (GS116) 16-Port Gigabit Ethernet Unmanaged Switch. If flapping happens at short intervals, it can cause a spike in the CPU utilization as well. conf configuration from duid to clientid and then reboot. 1 on Isilon Gen 6 nodes on the VxBlock System 1000 and as a storage technology extension for the VxBlock Systems 350, 540, and 740. In FreeNAS 11. It also causes STP to recalculate if running Layer2 services on those ports or a routing protocol to converge if running Layer3 services along with dynamic routing. So I've tried that but since The options for SET team Load Balancing distribution mode are Hyper-V Port and Dynamic. It looks like a switch issue to me, there dont appear to be any loops - that i can see. Allows the switch to be directly connected to a network, enabling plug-and-play operation. Has plenty of features, but port flapping hell! Unstable, random disconnections, floods network, experiencing packet loss between clients connected to the same switch. This connection link drops ever 2 minutes exactly from the NV4116E-HS side. This safeguards the switch during that time, if the problem happened to be a once off issue. 991c. The switch cannot send or receive protocol packets. Flapping With IP Hash, you must have a port-channel (sometimes called etherchannel or ‘trunk’ in the HP world), otherwise you will see MAC-flapping on the physical switch and some other oddities. 091 […] I’ve been having a problem with ethernet port flapping on numerous B5c and B5 radios. Jump to Latest Follow Status Not open for further replies. 47. There is a known problem with \ the 2208 and the 2216 in case proxy IPs are used. 0 build 22. 923 EDT: %SW_MATM-4-MACFLAP_NOTIF: Host 9c8e. Detect topology changes and automatically generate a new loop-free topology. When using Hyper-V Port mode for SET teams, the Hyper-V Virtual Switch port and the associated MAC address are used to divide network traffic between SET team members. R500 APs port flapping on Cisco Switch. XXXX is flapping between ports on the same VLAN (these ports are shared between multiple Virtual Systems of a VSX Cluster). It's AWESOME! I'm not doing a project for a relative and he doesn't quite need 24 ports. and the MAC address-table would become: I reloaded one of the rack switches 10 times in a row (no config changes in between) and got it to re-produce the port-flapping problem twice. > vlan 104 is flapping between port Gi1/0/28 and port Gi1/0/27 What's behind these ports? The switch is complaining that the MAC address keeps moving. To view Disabled Ports: Port up for 11 seconds Hardware is GigabitEthernet, address is cc4e. It seems there is another new Checkpoint cluster connecting to same switch and not considering Magic Mac Address Conflicting. Sep 14 13:48:28. I note that the problem is worse with some Canon Printers, Condition: The Catalyst 3750 switch if operated in a high temperature environment for a number of years may exhibit stack port flapping, fixed port flapping, traffic loss, or fail to function after operating without problems. Faulty cables and/or SFP+ modules are the most common cause of these errors. Fix Ethernet Port Flapping on MikroTik RB3011. If I reboot the server it will stay up for 5-7 days and then start doing it again. Hello, I have 4x R500 APs with a 1200 Zone Director on version 9. An access port can be assigned to only one VLAN. Note that flapping here is between port 4 (phy-br-ex) and 5 (eth4). When establishing a management link to the Dell PowerEdge VRTX Chassis Management Controller (CMC), it is recommended to create a separate VLAN. In the absence of a DHCP server on the network, the switch falls back to the static address 192. 6e00 in vlan 50 is flapping between port Gi0/1 and port Gi0/2</code></p> i changed port on Cisco switch from port1 to port2 connected to RB3011UiAS-RM and i changed port on RB3011UiAS-RM from ether4 to ether5 connected to cisco switch, both with no success. To enable err-disabled ports on Cisco 3750 switch series. I noticed on my switch several messages like this: %SW_MATM-4-MACFLAP_NOTIF: Host xxxx in vlan 100 is flapping between port Gi0/9 and port Gi0/10 %SW_MATM-4-MACFLAP_NOTIF: Host xxxx in vlan 100 is flapping between port Gi0/10 and port Gi0/9. multiple connections between two network switches or two Bonding on this server flaps with the following messages seen in switch logs. The MAC-ADDRESS that is flapping is the virtual MAC-ADDRESS of physical port that is patched into the switch at site two (right hand side as you look at the diagram). The RB3011 contains two switch chips, both being the QCA8337 switch chip. A switching loop or bridge loop occurs in computer networks when there is more than one Layer 2 (OSI model) path between two endpoints (e. The priority of the edge switches stays at 8 (32768), so they won't ever become root. Example of a show LACP listing. I have 2 physical cisco switches. If the interface is up, make sure that you're using the same type of aggregation that the oracle switch expects. Visit next lesson to learn How to prevent MAC flooding attacks by configuring port security in Cisco Switches. FreeNAS Versions Configuration, SFP Whitelist, ARC automatic ring configuration (MRP), automatic port shutdown (link flapping) Security Port Security (IP und MAC) with multiple addresses(50 MACs per port), SNMP V3, SSH, Authentication (IEEE802. If using vSwitch NIC teaming with two or more physical NIC ports (vmnics) connected still only one copy of the tagged broadcast frame will be sent from the vSwitch. 1x Multi Cliant Authentication, Guest VLAN and Unauthenticated VLAN, Port based Radius VLAN assignment If you remember a while back, I posted looking for a 24-port managed switch. Figure 4 shows the port side of the 8/80 SAN Switch. Technical Tip for Intel x722 10Gb SFP+ NIC port link flapping when connected to Cisco SX550/SX350 switch LAN port Flapping MasterOogway. So reading some threads here I saw that one of the recommendations was to change the /etc/dhcpd. switchport trunk {encapsulation { dot1q } Sets the trunk characteristics when the interface is in trunking If only the TC (Send) statistics increase, topology changes occur on the switch. This state could be caused by a flapping port or a high amount of bad frames (CRC errors), which could indicate a problem with the media. In order to hit this issue, at least one condition should be met as described in the section below. Ensure that the TP is enabled on the switch. Please help me determine what cause this problem and how i can solve it. Follows is few logs: 07-Aug-2019 15:16:33 :%STP-W-PORTSTATUS: fa21: STP status Forwarding 07-Aug-2019 15:16:28 :%LINK-I-Up: fa21 Configurations Show Running Configuration (ubnt1)# show running-config Show Saved Configuration (ubnt1)# show startup-config Save Running Config to Startup Config (ubnt1) # write memory VLANs Create a VLAN (ubnt1) # vlan database (ubnt1) (Vlan)# vlan 10 (ubnt1) (Vlan)# vlan name 10 &quot;Voice&quot; Add Port to VLAN (ubnt1) # configure (ubnt1) (Config)# interface Over the past couple of days I noticed my internet downloads were much slower than before. . 7716 in vlan 11 is flapping between port Gi0/7 and port Gi0/11 • Increased traffic congestion at the switch and router layer. You should, if possible have the "primary" velop directly connected to the router on ethernet port 1, and the "primary" velop ethernet port 2 connected to the first switch; you choice. I tested this by enabling DTP again (By removing the switchport nonegotiate) command, and the flapping returned. After the MAC address flapping action is configured on an interface, if the switch detects MAC address flapping on the interface, it sets the physical status of the interface I have two Aristia 7150S-R that are mlagged together and I have all my servers using bonds across the mlagged switches. Lists a subset of configuration data for all ports on the switch; that is, for each port, the display shows whether the port is enabled, the operating mode, and whether it is configured for flow control. Switch Port Configuration – Speed and Duplex Some switch interfaces are fixed at a single speed. If I didn't experience major port flapping issues I'd give it a 4/5 because it has all the features I need, even though not very well implemented. Frequent status changes on an interface can lead to: STP topology recalculation and changes, Cisco UCS LACP Port Channel Flapping April 14, 2018 I recently encountered this issue during a deployment and wasn't able to find much information about it on the Internet, so I figured I'd make a quick blog post to document the issue and the solution in case other people encounter the same issue. To be clearer, my understanding is that the hub was patched into the switch via an uplink port not just plugged in, and the switch No other syslog messages can be seen on the switch, only MACFLAP and ofcorse if the interface becomes down or up. Cause Cluster correction packets are being forwarded between the cluster members with a fixed source MAC address: 02:00:00:00:00:mem_id Port flapping (port going UP and DOWN continually) can be caused by a faulty cable, link failure, active/standby switchover, port hardware failure, etc. If I didn't experience major port flapping issues I'd give it a 4/5 because it has all the features I need, even though not very well implemented. mac-address flapping detection security-level low. We’ve used shielded Cat6 at all sites and equipment is properly grounded with shielded RJ45 connectors properly terminated. It's an Inateck ultra mini USB HUB. mac-address flapping aging-time. Communities. 1 - 2 of 2 Posts. 0c ) and the target ports on the appliance (port 1 on slots 5 & 6). To verify port state. RSTP (Rapid Spanning Tree Protocol) provides the same features as STP. This article explains the Errdisable feature on Cisco Catalyst switches. the port channel goes into err disabled mode on the 6500, it comes back up after a manual no shut is done. It could be a loop, but most often (in my experience) it's "misconfigured" hosts, e. Ports turning up (on) and down (off) rapidly. BPDU data is still received in blocking state. Go to another system on the network and ping the recorded address to see if it responds. On B-SW01 it is learning from Port-channel10 (MLAG) but on B-SW02 it is learning from VX1 interface (vxlan) which is coming from the RR via B-SW01 and then beacon probes 1 beacon probing 2 beacons 1 flapping 1 port channels 1 Recently, someone asked me why when using VMware ESX with port-channel and beacon probes causes mac-flapping. Usually, but not always, the link will go down again either immediately or shortly thereafter, and the process will repeat. As suggested and confirmed by Skirk1983. As soon as there is traffic I have installed 15 new X460 switch stacks, and upgraded the Firmware on some old X450s. It is not uncommon in the early development of an Ethernet Switch for a prototype switch to exhibit what is known as a “link flap. Obviously I cant plug in 16 cameras to 8 ports, so i have a link from the NVR to a managed 24 port POE switch. 3. When MAC address flapping occurs on a user network because of loops, you can configure a loop prevention action for the switch to perform when MAC address flapping occurs. 0 0. This panic affects \ ONLY 2208 and 2216 switch types. I notice that many of the Ethernet Ports are "Flapping". 5. 0. we have arp inspection &a MAC flapping is when a source MAC address is seen on different ports. Route flapping can be contained to a smaller area of the network if route aggregation is used. Yes, access ports for workstations will flap as computers turn on and off. Port Flapping can affect latency if the ports are part of the transit flow. Now the problem is, when i 'no shut' both ports on the router connected to the switches, it all works well for 20secs and i can even ping succesfully, but then is comes up saying that the po1 port is flapping with port such and such and then both ports goto into err Port switch is flapping due to similar MAC address 02:00:00 of multiple different cluster members in the same network segment. 1. Symptoms If you apply a default speed setting of 1G, then disable an interface for 10G/1G SFP media ports, this can lead to link flapping side effects with certain peer switches (such as Cisco). The reason for this is due to the fact that switch learns of a particular clients mac from one particular port to which the AP is connected to. FS S3800-24T4S stack switch is this kind of 1000BASE-T switch, which comes with a console port, 24 *10/100/1000BASE-T RJ45 ports and 4 *10GbE SFP+ ports. This Server NIC 0 is connected with Switch port 1/0/18 and NIC 1 is connected with Switch port 2/0/18, In this environment, we have two switches configured as a stack so we have to use one port Block specific ports of the switches to build a loop-free topology. Have a nice day We have already discussed about, Brocade SAN switch Zoning steps Via CLI and CISCO MDS Zoning steps via CLI This write-up, focuses on the basic trouble shooting commands used in Brocade SAN switch. RE: How to troubleshoop flapping ports? The SG300 switches do not support DTP and all trunks are run with Switchport mode trunk by default. The Cisco's are logging flapping on most of the ports with AP's attached to them. Dear, I have a problem for a week, charges that the switch ports is flapping, just for good measure that these interfaces were disconnected and caused a big problem. Catalyst 3750 Switch Command Reference 78-15165-02 dot1x default 2-65 dot1x guest-vlan 2-66 dot1x host-mode 2-67 dot1x initialize 2-69 dot1x max-req 2-70 dot1x multiple-hosts 2-71 dot1x port-control 2-72 dot1x re-authenticate 2-74 dot1x re-authentication 2-75 dot1x reauthentication 2-76 dot1x system-auth-control 2-77 dot1x timeout 2-78 duplex 2-80 For example, I saw an issue where the last two ports on the outer edge of a layer-3 switch encountered a problem with flapping interfaces. I have a 2960 switch and every then and now the ports are flapping, while i was on console i saw ports going down and coming up when the ping to machine ip addresses timed out the port status on switch was still up no errors collisions seen on sw port. A trunk is a point-to-point link between two switches or between a switch and a router. I investigated further and discovered my LAN connection was working at 100Base-T whereas before it had been a 1000Base-T. Edge ports do not register any incoming BPDU activities. 565d. MAC address flapping between interfaces may be not caused by network loops. In the MAC address entry with MAC address 0011-0022-0034 and VLAN 2, the outbound interface is changed from GE 0/0/1 to GE 0/0/2. we are running pvstp+ on this cisco box. A link flapping event is defined as a link that goes down and comes back up (usually immediately) with no user intervention. Now the problem is, when i 'no shut' both ports on the router connected to the switches, it all works well for 20secs and i can even ping succesfully, but then is comes up saying that the po1 port is flapping with port such and such and then both ports goto into err Can you run a show port-channel summary from the cisco switch and see if the port actually came up? You may need to interface port-channel# and then no shutdown (for each interface). The trunk port sends and receives encapsulated (tagged) frames that identify the VLAN of origination. Can you try to move one of the flapping devices to another switch to see if it will continue to flap, this is the fastest way to check who is going crazy. 0000. port 4 is phy-br-ex which is internal ovs port and not bond slave which has no associated vlan configuration on switch/blade. The trunk port sends and receives encapsulated (tagged) frames that identify the VLAN of origination. After port isolation is configured, ports are isolated at Layer 2 but can communicate at Layer 3 by default. 4 release notes: \ Q01389286 PANIC: 2208/2216 switches may panic when Proxy IP address are being used and the \ switch receives an ICMP echo request sent to the Proxy IP address. what could be the reason for its frequent flaps. Additionally, you might want to protect the root ports on the edge switches so that no rogue switch can grab the root. Actually it was experienced before when configured ClusterXL. If you see these messages frequently for a particular port, the link is flapping, which means that the link is constantly lost and regained. 499: %SW_MATM-4-MACFLAP_NOTIF: Host 0050. aaaa. Hyper-V Port. Tagged frames from VMs are dropped You should then see CAM table flapping ('MAC flapping') reported by the switch. Disabled - Does not participate in STP, the switch port is administratively disabled. The Cisco SG200-26, a sub $300 switch has 24 ports, plus 2 SFP ports. If not, most likely you have to work on your router configuration. Hyper-V will assign 802. Has plenty of features, but port flapping hell! Unstable, random disconnections, floods network, experiencing packet loss between clients connected to the same switch. 1. Each 6248 has two links to each 5548. The port flapping frequency is not constant. Edge ports assume Designated port roles. The minor port flapping is odd but I'd not jump to conclusions just yet. I was attaching a headless test device to a 3750G and I couldn’t see the status of the NIC from the tester’s perspective. I have seen identical IP addresses constantly battling it out on the network, toggling network access back and forth causing similar flapping. I have a syslog running which appears to show "port flapping" - all the switches are older HP V1910 or A5500 The ports that are flapping always appear to be different - is this common? The switch has behaved fine. Switch Logs: 655033: . The APs are connected to a Cisco WS-C2960X To check for this, record the IP address of the flapping port, then unplug the flapping port from the network. -B I have the NV4116E-HS, which is a 16 port nvr, the unit has a built in 8 port poe switch on the back. Troubleshooting the situation, I found that the switch stackwise ports were flapping. Lists the current operating status for all ports on the switch. If the problem is regularly occurring on a particular interface, you should perform testing in a controlled fashion during a change window, to isolate the faulty component by swapping cables, modules, and switch ports as needed to isolate the issue. Hi i have been recevied this message from two of my access ports. Converged Systems documentation was updated to support: PowerScale OneFS 9. Oct 1 11:48:27. Edge ports are ports of a bridge that connect to workstations or computers. If you are using the load balancing channel bonding, your router may complaint that the MAC address is flip flopping because the same MAC address is appearing in two different links. Netgear support not very helpful. 773: %SW_MATM-4-MACFLAP_NOTIF: Host 6420. The 5548 is configured with virtual port channels, so each VPC represents one 6248. I spent 30 minutes troubleshooting a flapping switch port in the lab this week. However, the Palo Alto firewall should recognize the change of MAC addresses from one physical port to another. There should be similar functions on the Cisco switch. • Trunk Ports for link to other switches and router Port 1 –Link to router Port 2 –Link to next switch • Access ports for the servers, PCs and phones Ports 3-6 –PCs and Phones Port 7 –Untagged in VLAN11 for a server Port 8 –Untagged in VLAN201 for public device 17 When the > VLAN bounces back to port 4, the switch accepts that VLAN and the packets go > through. As we notice below the port is flapping a decent amount of times and we get this… After creating MLAG with the TOR Stack switches, all MAC addresses have started flapping. </p> <p>Example of a log from Cisco switch:<br/> <code>MACFLAP_NOTIF: Host 0000. a host with dual NICs that's using some kind of load-sharing between ports. switch ports flapping


Switch ports flapping