SG500-52 5 Member Random Stack Drop

[BJM]

Hopefully someone has an idea on this.  5 member SG500-52 stack using Native Stacking with all connection speeds set to Auto (Stack Master set to Auto as well).

Every so often, all switches (with the exception of the master - S1) will reset.  When the issue starts, the logs look like this:

%CSCDLAG-W-DOWN: Stack port S4 operational status is Down

%FFO-W-FFO-ACTIVE: Fast Failover is triggered

%CSCDLAG-W-DOWN: Stack port S3 operational status is Down

%MLDP-W-ABORT: Connection to Unit 2 is aborted due to Stack Management notification. (this will repeat for units 3-5)

%LINK-W-Not Present:  gi2/1/1 (this will repeat for all ports gi2-5/1/1-50)

S1 does not go down, but it takes about 5-10 minutes for the resets on the other units to complete and rejoin the stack and all is well in the world until it happens again.  

Active Firmware is 1.4.7.6 (I need to update to 1.4.8.6).  But does anyone have any other ideas on what might cause this or what to look for?

Thanks for any help!

[Glenn Martin]

Hello BJM,

Do they all reset collectively? You mentioned the Master doesn't go down, but what about the backup?  

Just checking a few obvious things:

• Have you tried swapping out the Stack cables? I would recommend this first

Let me knwo if this helps or we might need to escalat to the TAC.

Thanks,

Glenn

[BJM]

Glenn,

Thanks for your response. Switches other than the master all seem to reset (2-5). The stack uptime doesn't reset, so 1 seems to stay up. All stacking cables are Cisco oem, which one would you suggest swapping out? (Hopefully not all...)

Thanks for your thoughts on this!

[Glenn Martin]

What configuration are you implementing - Ring or Chain?

• Try swapping the master Backup cable
• Also try making another device the Master
• how often does this happen and is there a pattern?

As mentioned, for further investigatoin I would surely recommend contacting the Technical Services team.

Thanks

Glenn