2 NIC cards on a server

Chiefcrowe

Diamond Member
Sep 15, 2008
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In windows 2008 R2 environment, i have a server that has 2 NIC cards. They both connect to the same switch but they are 2 different subnets (10.1.100 and 10.1.101). I was wondering, if i use the gateways of 10.1.100.1 and 10.1.101.1, will there be any issues?
thanks,
 

classy

Lifer
Oct 12, 1999
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In windows 2008 R2 environment, i have a server that has 2 NIC cards. They both connect to the same switch but they are 2 different subnets (10.1.100 and 10.1.101). I was wondering, if i use the gateways of 10.1.100.1 and 10.1.101.1, will there be any issues?
thanks,

In most cases yes. Multiple gateways on a server functioning only as a server is bad unless properly setup. Indy posted how to make it work.
 
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Chiefcrowe

Diamond Member
Sep 15, 2008
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Thanks for the replies. So, generally one should use the same gateway for the 2 subnets?
they both are on the same switch and can communicate with each other fine and so far i have not seen any issues. This network (both subnets) is internal only and cannot be accessed from the outside (without a vpn).
I was asked to use a different subnet because of a new San device added to our area.
 

seepy83

Platinum Member
Nov 12, 2003
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You most likely don't need to define a Default Gateway for the SAN subnet. The default gateway is used when the host doesn't know where to send the packet (i.e. it's trying to send to a device on another network/subnet and needs to use a routing device (default gateway) to get the packets there).
 

imagoon

Diamond Member
Feb 19, 2003
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Don't define gateways on the SAN network. There is rarely a reason to do so (on the clients at least.) The SAN itself might have a gateway setting (and may support one for each network) but that is typically for SAN to SAN replication. Also... They should be completely isolated. There is no reason to even support a VPN connection to them The SAN will have a management port(s). Those should be connected to an accessible service network. The iSCSI networks should not be. In most cases you will be using specialized ethernet settings that will not survive well in the regular network and you have to consider security because someone can access "raw disk" if they can connect to the targets.
 
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Emulex

Diamond Member
Jan 28, 2001
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you need to define a gateway for a san network but you should never need to use it. even vcenter asks for one but it doesn't make any sense.
 

imagoon

Diamond Member
Feb 19, 2003
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you need to define a gateway for a san network but you should never need to use it. even vcenter asks for one but it doesn't make any sense.

All of my vcenter servers, esxi hosts and windows boxes on SANs do not have gateway addresses on the san networks. It never asked nor required it anywhere.