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ErrDisable message

I was upgrade a LAN. I have a Catalyst 2950, a router 2509 and two other switches (DLINK DES 1016D). The topology is like this : WAN/Internet -> 2509 -> other switch_1 -> other switch_2 -> 2950.

The server is connected to 2950. The platform of server is Novell 4.

All ports in switch was connected to client and server (switch_2 use port 1).

I have configured the IP address to 2950.

At the first time I start the LAN, all client would not login to the server, so I configured the 2950 for all ports except port 1 (connected to switch_2):

2950(config-if)#spanning-tree portfast.

The problem was solved.

But after several days, port 1 (connected to switch_2) and several ports connected to client were down, there is message "errdisable". How to solve this problem ?

The features of other switch (DLINK) are:

-16x 10/100 mbps, autonegotiation ethernet port

-auto MDI/MDI-X for each port

-wire speed reception and transmission

-store-and-forward switching method

-integration address look-up engine support 8k absolute MAC address

-support 4 mbits RAM for data buffers

-extensive front panel diagnostic LED

-IEEE 802.3x flow control for full-duplex

-back pressure flow control for half-duplex

Cisco Employee

Re: ErrDisable message

You may be able to find out what condition detected to errdisable the ports by looking at the logging buffer (show logging).

Also you can show what conditions the switch looks for to errdisable ports with 'show errdisable detect'

sample output:

Switch#show errdisable detect

ErrDisable Reason Detection status

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

pagp-flap Enabled

dtp-flap Enabled

link-flap Enabled

l2ptguard Enabled

gbic-invalid Enabled

loopback Enabled

Moreover, you can configure the switch to automatically recover from this condition.

'show errdisable recovery' shows what conditions the switch will automatically recover from.

example output:

Switch#show errdisable recovery

ErrDisable Reason Timer Status

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

udld Disabled

bpduguard Disabled

security-violatio Disabled

channel-misconfig Disabled

vmps Disabled

pagp-flap Disabled

dtp-flap Disabled

link-flap Disabled

gbic-invalid Disabled

l2ptguard Disabled

psecure-violation Disabled

loopback Disabled

you can enable automatic recovery for individual conditions or globally. Example below:

Switch(config)#errdisable recovery cause ?

all Enable timer to recover from all causes

bpduguard Enable timer to recover from BPDU Guard error disable


channel-misconfig Enable timer to recover from channel misconfig disable


dtp-flap Enable timer to recover from dtp-flap error disable state

gbic-invalid Enable timer to recover from invalid GBIC error disable


l2ptguard Enable timer to recover from l2protocol-tunnel error

disable state

link-flap Enable timer to recover from link-flap error disable


loopback Enable timer to recover from loopback detected disable


pagp-flap Enable timer to recover from pagp-flap error disable


psecure-violation Enable timer to recover from psecure violation disable


security-violation Enable timer to recover from 802.1x violation disable


udld Enable timer to recover from udld error disable state

vmps Enable timer to recover from vmps shutdown error disable


hope that helps