Performance Question - cisco WS-C6504-E

[miceve]

Hello all,

i think about a backup infrstructure scenario. The "backup-server" should backup VMs from an ESX host in an ESX-NET Network and stores it to a storage in BACKUP-NET network.

We have a third network (in this example) - SERVER-NET network - for all general servers. 

The SERVER-NET and ESX-NET are both directly routed on the core switch and no ACLs are defined deny'ing any kind of traffic flow (in this szenario)

QUESTION: Does it make much of a performance impact to put the backup server into a "SERVER-NET" where it needs to go over the CORE Switch "the Gateway of SERVER-NET" in order to access the ESX-NET. Or would it make more sense to put the backup server directly into the "ESX-NET" network. [I want to avoid that cause it is not the purpose of this network to have other systems than ESX Servers]

Thank you for your suggestions in advance!

BR Michelle 

[balaji.bandi]

personally i would suggest Storage and backup in same VLAN where possible to increase the performance.

in your explanation i am bit confused, can you elaborate with VLAN or IP address so we can easily understand.

[miceve]

Backup-Server and Backup Storage are in the Same VLAN20 BACKUP-NET (192.168.22.0/24) (not routed at all directly connected through a switch). -> That is fix given. (The Backup-Server's first network interface is directly connected to that VLAN20)

The networks - routed by the CoreSwitch (Cisco 6500) are:
VLAN101 - SERVER-NET (10.0.1.0/24);
VLAN420 - ESX-NET (10.4.20.0/24)

An ESX Server 10.4.20.22 running VMs is in an ESX-NET  network.
To backup the VMs, the Backup-Server needs to connect to the ESX Server in "ESX-NET"

Question: in which network should i put the second network interface of the Backup-Server. 

OptionA: Directly connect the second network interface of the Backup-Server to the VLAN 420 "ESX-NET" 
OptionB(prefered): Put the second network interface of the Backup-Server into the VLAN101 "SERVER-NET" - to get to the ESX Server it has to go over the Default Gateway 10.0.1.1 (CoreSwitch) to get to the ESX Server 10.4.20.22.

FollowUpQuestion: Is it much of a performance difference between OptionB and Option A? (Option A is Layer 2 Switching; OptionB is Layer 3 Routing [but on a core switch though])

I hope this is a little bit clearer now. Thank you very much for that fast response.

[balaji.bandi]

Since VM has capabilities adding another Interface which is not routable, that interface and IP belowing to same backup vlan should be good. (is this works i belive you are in the same line of what i am thinking)

[miceve]

No the backup lan is not the issue. It is already decided that backup server and backup storage are on a same network. This is given.

-> The backup-server backups the VMs from the ESX and stores them on a backup storage in the backup network.
The question is how to connect Backup-Server AND  ESX Server - should i go Layer 2 via direct connection of the Backup-Server's second network interface to the ESX-NET
OR
Layer 3 in a separate network which needs to be routed on my core switch to get to the ESX Server in ESX-NET. I would prefer Layer 3 in a separate network (SERVER-NET) but fear of a performance issue on my core switch.

BR Michelle