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Important outage with SG300-8


I have a small SG300-8 switch to connect 1Gbps Internet Connection to a router and a server console. Today we have suffered a network outage and I don't know the reason and if it has been related with the switch model.

Since this afternoon I have a great number of packet losses between the ISP and our switch. So many losses that I couldn't connect to any device (switch, router, service console) from Internet and we have completely lost internet connection. The ISP have told me that he was receiving a great number of input errors (mainly CRC errors) in his network interface. But suddenly it has begun working again.

I have only these logs from the switch and I'm very worried about this problem. The logs of the switch:

5-Jun-2012 03:23:01 :%STP-W-PORTSTATUS: gi2: STP status Forwarding

15-Jun-2012 03:22:57 :%LINK-I-Up:  gi2

15-Jun-2012 03:17:41 :%LINK-W-Down:  gi2, aggregated (1)

15-Jun-2012 03:13:09 :%STP-W-PORTSTATUS: gi2: STP status Forwarding

15-Jun-2012 03:13:05 :%LINK-I-Up:  gi2

15-Jun-2012 03:13:02 :%LINK-W-Down:  gi2

15-Jun-2012 03:10:10 :%STP-W-PORTSTATUS: gi1: STP status Forwarding

15-Jun-2012 03:10:06 :%LINK-I-Up:  gi1

15-Jun-2012 03:00:23 :%STP-W-PORTSTATUS: gi2: STP status Forwarding

15-Jun-2012 03:00:18 :%LINK-I-Up:  gi2

15-Jun-2012 03:00:16 :%LINK-W-Down:  gi2

15-Jun-2012 02:59:32 :%LINK-W-Down:  gi1

14-Jun-2012 22:13:02 :%STP-W-PORTSTATUS: gi1: STP status Forwarding

14-Jun-2012 22:12:58 :%LINK-I-Up:  gi1

14-Jun-2012 21:55:08 :%STP-W-PORTSTATUS: gi2: STP status Forwarding

The only thing that I don't understand is the meaning of "agregated". The port gi2 is where ISP was connected. I would appriciate any comment, any! Thanks is advance, I would try to sleep...


3 Replies 3


It seems that i have errors in that interface...

m-globalswitch-sw-1#sh interfaces counters gi2

      Port       InUcastPkts  InMcastPkts  InBcastPkts    InOctets

---------------- ------------ ------------ ------------ ------------

      gi2          3996281         10          1468      1234443603

      Port       OutUcastPkts OutMcastPkts OutBcastPkts  OutOctets

---------------- ------------ ------------ ------------ ------------

      gi2          8270438       14598          8        3626646129

Alignment Errors: 0

FCS Errors: 2125724

Single Collision Frames: 0

Multiple Collision Frames: 0

SQE Test Errors: 0

Deferred Transmissions: 0

Late Collisions: 0

Excessive Collisions: 0

Carrier Sense Errors: 0

Oversize Packets: 0

Internal MAC Rx Errors: 0

Symbol Errors: 0

Received Pause Frames: 0

Hi Christian,

What caught my eye was:

FCS Errors: 2125724

What device is gi2 connected to? It looks like there may be a port setting mismatch (ie full duplex v. half duplex) that may be causing the checksum errors.  Can also look at the output from show spanning-tree detail.

Don't forget, you can always try cisco small biz support via chat. They are top notch.



Please rate helpful posts.

ok. Thanks David.

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