Random UP/DOWN: all ports

[Miyo360]

• 2 x 1920-24G-PoE+ (JG925A)
• Latest firmware
• Rebooted yesterday

Hi,

For the past two days I have complaints from my users in a remote office. They are losing network connectivity for a few minutes at a time. When they get a connection back, another user pops up complaining of lost connection.

The syslog shows ports are randomly flapping up/down for a few minutes, then stablising. Then another port is affected. Over the course of about an hour, pretty much all users will be affected. These ports are mainly filled with desktop computers running a mix of Intel, Broadcom and Realtek NICs.

Here is a sample from the syslog

<188>1 2017-12-20T22:47:40+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.3: Interface 18911232 is Down, ifAdminStatus is 1, ifOperStatus is 2  
<187>1 2017-12-20T22:47:40+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is DOWN.
<188>1 2017-12-20T22:47:46+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.4: Interface 18911232 is Up, ifAdminStatus is 1, ifOperStatus is 1  
<187>1 2017-12-20T22:47:46+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is UP.
<185>1 2017-12-20T22:47:46+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/1/PFWD(t):   Trap 1.3.6.1.4.1.25506.8.35.14.0.1: Instance 0's Port 0.18911232 has been set to forwarding state!
<190>1 2017-12-20T22:47:46+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/6/MSTP_FORWARDING(l): Instance 0's port GigabitEthernet1/0/10 has been set to forwarding state.
<188>1 2017-12-20T22:48:36+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.3: Interface 18911232 is Down, ifAdminStatus is 1, ifOperStatus is 2  
<187>1 2017-12-20T22:48:36+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is DOWN.
<188>1 2017-12-20T22:48:41+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.4: Interface 18911232 is Up, ifAdminStatus is 1, ifOperStatus is 1  
<187>1 2017-12-20T22:48:41+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is UP.
<185>1 2017-12-20T22:48:41+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/1/PFWD(t):   Trap 1.3.6.1.4.1.25506.8.35.14.0.1: Instance 0's Port 0.18911232 has been set to forwarding state!
<190>1 2017-12-20T22:48:41+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/6/MSTP_FORWARDING(l): Instance 0's port GigabitEthernet1/0/10 has been set to forwarding state.
<188>1 2017-12-20T22:54:12+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.3: Interface 18911232 is Down, ifAdminStatus is 1, ifOperStatus is 2  
<187>1 2017-12-20T22:54:12+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is DOWN.
<188>1 2017-12-20T22:54:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.4: Interface 18911232 is Up, ifAdminStatus is 1, ifOperStatus is 1  
<187>1 2017-12-20T22:54:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is UP.
<185>1 2017-12-20T22:54:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/1/PFWD(t):   Trap 1.3.6.1.4.1.25506.8.35.14.0.1: Instance 0's Port 0.18911232 has been set to forwarding state!
<190>1 2017-12-20T22:54:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/6/MSTP_FORWARDING(l): Instance 0's port GigabitEthernet1/0/10 has been set to forwarding state.
<188>1 2017-12-20T23:16:13+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.3: Interface 18874368 is Down, ifAdminStatus is 1, ifOperStatus is 2  
<187>1 2017-12-20T23:16:13+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/1 link status is DOWN.
<188>1 2017-12-20T23:16:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.4: Interface 18874368 is Up, ifAdminStatus is 1, ifOperStatus is 1  
<187>1 2017-12-20T23:16:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/1 link status is UP.
<185>1 2017-12-20T23:16:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/1/PFWD(t):   Trap 1.3.6.1.4.1.25506.8.35.14.0.1: Instance 0's Port 0.18874368 has been set to forwarding state!
<190>1 2017-12-20T23:16:15+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/6/MSTP_FORWARDING(l): Instance 0's port GigabitEthernet1/0/1 has been set to forwarding state.
<188>1 2017-12-20T23:18:50+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.3: Interface 18911232 is Down, ifAdminStatus is 1, ifOperStatus is 2  
<187>1 2017-12-20T23:18:50+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is DOWN.
<188>1 2017-12-20T23:18:57+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.4: Interface 18911232 is Up, ifAdminStatus is 1, ifOperStatus is 1  
<187>1 2017-12-20T23:18:57+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is UP.
<185>1 2017-12-20T23:18:57+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/1/PFWD(t):   Trap 1.3.6.1.4.1.25506.8.35.14.0.1: Instance 0's Port 0.18911232 has been set to forwarding state!
<190>1 2017-12-20T23:18:57+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/6/MSTP_FORWARDING(l): Instance 0's port GigabitEthernet1/0/10 has been set to forwarding state.
<188>1 2017-12-20T23:20:10+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.3: Interface 18911232 is Down, ifAdminStatus is 1, ifOperStatus is 2  
<187>1 2017-12-20T23:20:10+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is DOWN.
<188>1 2017-12-20T23:20:13+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.4: Interface 18911232 is Up, ifAdminStatus is 1, ifOperStatus is 1  
<187>1 2017-12-20T23:20:13+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/10 link status is UP.
<185>1 2017-12-20T23:20:13+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/1/PFWD(t):   Trap 1.3.6.1.4.1.25506.8.35.14.0.1: Instance 0's Port 0.18911232 has been set to forwarding state!
<190>1 2017-12-20T23:20:13+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10MSTP/6/MSTP_FORWARDING(l): Instance 0's port GigabitEthernet1/0/10 has been set to forwarding state.
<188>1 2017-12-20T23:34:52+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.3: Interface 18935808 is Down, ifAdminStatus is 1, ifOperStatus is 2  
<187>1 2017-12-20T23:34:52+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/16 link status is DOWN.
<188>1 2017-12-20T23:34:54+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/4/INTERFACE UPDOWN(t):   Trap 1.3.6.1.6.3.1.1.5.4: Interface 18935808 is Up, ifAdminStatus is 1, ifOperStatus is 1  
<187>1 2017-12-20T23:34:54+00:00 2017 HK-Switch1 - - - HK-Switch1 %%10IFNET/3/LINK_UPDOWN(l): GigabitEthernet1/0/16 link status is UP.

The topology is:

All endpoints (desktop PC) are plugged into HK-Switch1, ports 1-18.
Ports 19-24 are plugged into other network devices (a NAS, a photocopier, etc). Two ports are going to a single phyiscal server, running Hyper-V (one port for management, one for VM traffic). There are 3 VM's running on this host.

Upsteam this is plugged into a Meraki MX64 firewall (port 1)

I have a 2nd identical switch plugged into port 2 on the Meraki. I did have the hyper-v host plugged into both for fault tollerance, but have now disabled all ports on this switch, except the uplink port to the Meraki. The problems are still ongoing.

No changes have been made to either switch, the Meraki in months.

This problem does not appear to occur when the PC's are left on but no one using them. Due to a time difference, I have access to a quiet office for troubleshooting, but cannot get any of the ports to drop. I know that when my users arrive tomorrow, they will all start flapping again. 

I don't believe any rogue devices are being plugged in. The flapping would suggest an STP issue, but having disabled all the ports on the 2nd switch, I would expect this to be ruled out.

What else could be happening?

Thanks in advance.

[drk787]

Hi,

Do you still have the issue. 

Check the CPU utilization of the switch at the time of issue (may be if you have NMS configured)

If the CPU is normal, may be a support case need to be logged for deeper analys of the diagnostic log file.

Thank you