Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations Mike Lewis on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Cisco Sg-300 Flapping?

Status
Not open for further replies.

Hayden09

IS-IT--Management
Jan 19, 2024
2
CA
Hi All,

Earlier this week I had some sg-300's going up and down on multiple ports without any network changes been made.

I thankfully rebooted them after continuous network outages and it resolved the problem.

But I seem to have lingering issues with STP alerts coming up like so:

2147483232 2024-Jan-19 12:20:26 Warning %STP-W-PORTSTATUS: gi50: STP status Forwarding
2147483233 2024-Jan-19 12:19:56 Warning %STP-W-PORTSTATUS: gi44: STP status Forwarding, aggregated (1)
2147483234 2024-Jan-19 12:19:56 Warning %STP-W-PORTSTATUS: gi44: STP status Blocking, aggregated (1)
2147483235 2024-Jan-19 12:19:40 Warning %STP-W-PORTSTATUS: gi44: STP status Forwarding
2147483236 2024-Jan-19 12:19:40 Warning %STP-W-PORTSTATUS: gi50: STP status Blocking
2147483237 2024-Jan-19 12:19:40 Warning %STP-W-PORTSTATUS: gi44: STP status Blocking

Unfortunately there is no existing diagram of the network setup. So would my best first course of action be mapping the network and seeing if there is somehow a loop being created?

From my limited experience with Spanning Tree, I think there are multiple routes possible for some machines like our phone system and its occasionally causing the traffic problems.

I'm looking for some advice as to how I should trace these switches and find why STP status is blocking sometimes and then not at all for a while.

Thank you for your help!
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top