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multiple switches uplink failed

i hope someone can provide some clue.
all of sudden multiple cisco switches uplink failed with orange light and caused users inaccessible to network
after power cycle each switch, it was back to normal.
l checked show log but did not see any hint.
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Predrag Jovic
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all of sudden multiple cisco switches uplink failed with orange light and caused users inaccessible to network
That is typically happening when you add switch with better VTP revision into network - it overwrites all of your existing VLANs with VLANs on new switch.
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besides adding a new switch, would it be possible of configuring SPAN  monitor session on a port channel of 2 ge interfaces as source?
I forgot about one detail, restart in this case of higher VTP revision should not help. So I guess VTP should not cause this behavior.
In that case I can't think of mechanism to cause what you are describing.
Not sure about SPAN, but if you send 2Gb of traffic through 1 GB link it can cause problems for sure (but I guess not those that you described, at least not easy).
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in the switch that configured with monitor session on port channel, there was an error EC-5-UNSUITABLE: [chars] will not join any port-channel, [chars].
would it be something related?
That can be a problem. :)
Error Message    EC-5-UNSUITABLE: [chars] will not join any port-channel, [chars].

Explanation    This message means that one of the interfaces cannot join the EtherChannel because it is configured for PortFast, as a VLAN Membership Policy Server (VMPS), for 802.1X, as a voice VLAN, or as a Switched Port Analyzer (SPAN) destination port. All of these are unsuitable configurations for EtherChannels. The first [chars] is the interface name, and the second [chars] describes the details of the unsuitable configuration.

Recommended Action    Reconfigure the port; remove the unsuitable configuration.
Looks like traffic from port channel came to a wrong place.
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thanks for durther detail. so do you think it`s likely to cause STP blocking on issue that I had?
it was nit affect all switch but only some of them.
those affected switches were on differernt vlan from the one that configured for SPAN
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thanks for durther detail. so do you think it`s likely to cause STP blocking on issue that I had?
it was nit affect all switch but only some of them.
those affected switches were on differernt vlan from the one that configured for SPAN
so do you think it`s likely to cause STP blocking on issue that I had?
I guess STP could be root cause, or any of mechanisms that can err-disable port. However you restarted switch and ports were no longer in err-disable so you can establish root cause.
# show interface status err-disabled
can show you root cause in this case.
Also possible causes can be any of active err-disable mechanisms:

# show errdisable recovery
ErrDisable Reason    Timer Status
-----------------    --------------
udld
bpduguard
security-violatio
channel-misconfig
pagp-flap
dtp-flap
link-flap
l2ptguard
psecure-violation
gbic-invalid
dhcp-rate-limit
mac-limit
unicast-flood
arp-inspection
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I tried with the command you suggested. The first one show interface status err-disable but did not return anything.
Then show errdisable recovery and all items are showing disable.
Would it because those affected switches already back online? Therefore, there was not clue could be traced.
It was weird only 3-4 switches' uplink were failed and affect other 10 switches that had uplink to these 3-4 switches.
Even though I suspect it was due to the setup of SPAN on an interface (destination port) that was configured with switchport access to a vlan and set as spanning-tree portfast as well as root guard, how it was impacted to other switches?
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Predrag Jovic
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again...thanks so much! i believe those command you suggested would help.