Solved: CSM Bridging during Backups?

jcmattos1 · ‎01-07-2008

I have two questions? This might seem like some dumb questions but, we have dual CSM's 4.2.6 in 6509 IOS 12.2(18)SXF in bridge mode. 1st question is, we have backup clients on one network and the host on another. The host is on a vlan behind the CSM and the backup client is not. Correct me if im wrong, but from my knowledge traffic should not go through the CSM when accessing the server RIP's directly. But why, does the CSM portchannel260 get impacted during backups? Shouldn't it route through the MSFC first? 2nd question if the backup server and the host is both on the same network but different vlans will it still communicate thru the MSFC or CSM? Please advise...Thx!

Gilles Dufour · ‎01-08-2008

Usually in bridge mode, the default gateway of a device is a router (often the MSFC) behind the CSM. The CSM bridge the front vlan with the backend vlan.

So, even if the MSFC is the device that does the routing between your source and destination, this traffic still needs to go through the CSM.

Same if the source and destination are in the same subnet. If the source is in vlan X and the destination in vlan Y using the same subnet with the CSM bridging the 2, the traffic still needs to go through the CSM.

So, you should look at the CSM as an external device even if it sits in the same chassis as the MSFC.

Gilles.

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Gilles Dufour · ‎01-08-2008

Usually in bridge mode, the default gateway of a device is a router (often the MSFC) behind the CSM. The CSM bridge the front vlan with the backend vlan.

So, even if the MSFC is the device that does the routing between your source and destination, this traffic still needs to go through the CSM.

Same if the source and destination are in the same subnet. If the source is in vlan X and the destination in vlan Y using the same subnet with the CSM bridging the 2, the traffic still needs to go through the CSM.

So, you should look at the CSM as an external device even if it sits in the same chassis as the MSFC.

Gilles.

jcmattos1 · ‎01-08-2008

Interesting...Thx again Giles!