Hi,

My requirement is to transfer huge amount of data using FTP from one unix box to another.
And our server has 2 NIC cards ( 100Mbps/Full duplex ) one is considered as primary and other is used for only backups.

When I plna to transfer the files, how can I tell ftp to use only the backup NIC for data transfer ( I dont want to use the primary NIC card as it will be busy during the business hours ) .

thanks in advance.

Are both NICs on the same network? If not, it'd route on its own. Otherwise, you'll need to make the secondary NIC the gateway to wherever box you want to put your files to with the route command.

Firstly thanks for the reply.
I do have 2 different IP address i.e 2 different subnets.
So you mean to say that changing default Gateway is the only option ?

If you have 2 different IP addresses, cannot you just use the IP you want? [I must be missing something obvious here]

No, you're not. If the backup IPs are on the same subnet then traffic will go directly via the interfaces that a local to each other, ie backup NIC to backup NIC. Nothing needs to be done.

Let me try to explain it better:

If your NICs are connected to 2 different subnets and the server you are ftp'ing your data to is in the same subnet as the secondary NIC, you probably don't need to do anything. And I say probably, because I don't have specifics, i.e., don't know if the secondary NIC was properly routed from the get-go. Quickly looking at the output of netstat -rn will tell you

If your secondary NIC is NOT in the same subnet as the server you are ftp'g to, or both NICs are on the same subnet, then you need to use the route command to tell your box that all traffic to <ip you are ftp'g to> has to go through gateway <ip of your second NIC> , NOT THE DEFAULT gateway. You would be adding a new gateway, not changing the default gateway.