Abstract
1. In normal operation Gig 0/0/2 port is in Forwarding state and Gig 1/0/2 port is in Discarding state BUT whole ring becomes unreachable.
2. When manually shutdown Gig 0/0/2 port, then Gig 1/0/2 port goes in forwarding state and ring becomes reachable.
3. When Gig 1/0/2 port goes in Discarding state then again whole ring becomes unreachable.
Issue Description
1. In normal operation Gig 0/0/2 port is in Forwarding state and Gig 1/0/2 port is in Discarding state BUT whole ring becomes unreachable.
2. When manually shutdown Gig 0/0/2 port, then Gig 1/0/2 port goes in forwarding state and ring becomes reachable.
3. When Gig 1/0/2 port goes in Discarding state then again whole ring becomes unreachable.
below is the topo:
Handling Process
from our checking, customer configure ACL 4001 and apply it in system view. the last rule is set "rule permit"
acl name MAC 4001 <?xml:namespace prefix = "o" />
description for MAC ACL
rule 5 deny destination-mac 0180-c200-0000
rule 10 deny destination-mac 0180-c200-0001
rule 15 deny destination-mac 0180-c200-0002
rule 20 deny destination-mac 0180-c200-0003
rule 25 deny destination-mac 0100-0c00-0000
rule 30 deny destination-mac 0100-0ccc-cccc
rule 35 deny destination-mac 0100-0ccd-cdd0
rule 40 deny destination-mac 0100-0ccc-cccd
rule 45 deny destination-mac 0100-0ccd-cdce
rule 1000 permit
The device is S5300-LI which using marvel chip, there is some wrong with the implementation mechanism. When match the permit rule, then will not transmit the ERPS message.
And as our checking, customer just apply the acl 4001 in system view, other acl not apply in system view. so only this ACL will affect the ERPS service.
Root Cause
this issue is due to device named “pune-dig-cha-jaytub-r2-eas04” not transmit the ERPS message, so ring is unreachable when G0/0/2 port is in Forwarding state and G1/0/2 port is in Discarding state.
The device is S5300-LI which use marvel chip, there is some wrong with the implementation mechanism. When match the permit rule, then will not transmit the ERPS message.
Solution
with customer confirmation, the ACL 4001 is useless. so after removing the traffic-filter inbound with acl 4001 in system view. the ERPS works fine
