Link to home
Start Free TrialLog in
Avatar of eemoon
eemoon

asked on

Mac address in Nexus7K fex port

Hi, One Microsoft server is connected to two Nexus7K via its fex port eth100/1/1 in Nexus7K_1 and eth100/1/2 in Nexus7K separately. These two fex ports are all up as showed by command "show interface brief" and "show interface status". My question is in Nexus7K_2, we can see mac address in output of "show mac address-table interface ethernet100/1/2", but we cannot see any in ethernet100/1/1 in Nexus7K_1 by the command. I think the port 100/1/1 might have not been used before. Do you think so? Any other issue can cause the issue? Thank you
ASKER CERTIFIED SOLUTION
Avatar of Predrag Jovic
Predrag Jovic
Flag of Poland image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Avatar of eemoon
eemoon

ASKER

Thank you so much for your reply.

Most likely server's network cards are configured as Active/Standby - so network cards are not configured/working in Active/Active mode.
You are right. Someone is changing the Active/Active into Active/Standby. I checked the interface e100/1/1 has not inbound traffic, but only have a little outbound traffic. I think the server connected to e100/1/1 has been changed to standby status. Instead, e100/1/2 has both inbound and outbound traffic.

This can potentially lead to network problems due to mismatch between ARP timeout and CAM table age timer, this can cause intensive unicast flooding in the case that you have the same VLAN  configured on many switches.
I have not understand it completely. Can you give a little bit more explanation on this ? Thank you
For more details please read chapter
Asymmetric Routing (Unicast Flooding):

There is several more similar scenarios to this one, but this is the general idea.
Avatar of eemoon

ASKER

Thank you
You're welcome.