Friends

FTP Client creates 2 connection (1 for forming FTP session and other for data transfer) to FTP server.

FTP is not working fine from an application. I trapped the request at FTP Server, when it switch over to the data port, the client IP Address changes ie. while forming the FTP connection, client IP is x.x.x.80 and while connecting to the data-port (for transferrring data), the client IP changes to x.x.x.81.

I have 2 network cards configured in the client machine. If i disable 1 network card, it works fine.

But if i enable both the network card and form a ftp connection from a command prompt then it works fine.

Please let me know what can be the issue.

Thanks

Praveen

Regards

Praveen

You don't need two different connections, one is enough. The fact that at different stages in the process they are using different ports is irrelevant. Having two different connections and two network cards is just an unnecessary complication.

Stuart

StuartS is 100% correct. This is why when you disable one NIC it works.

I have 2 network cards configured in the client machine. If i disable 1 network card, it works fine.

FTP is well known tcp/ip. It cares not if you have 1 or 500 nic cards. The tcp/ip stack routes the requests.

It is an application issue. FTP is a protocol. An FTP client application might be called from another application or use it's own. The question is what is the application doing. Calling on the default ftp client, built-in client or a secondary installed client.

You would need to tell us what application is calling what client. See systernals site for helper apps.

I read it wrong and answer it wrong too. So get off my case you peanut.

I'm more in agreement with Jefro, but it could be a virtual adapter rather than the application.

It sounds like your PC is using both NICs which means you might have an adapter bonding the NICs for load balancing and/or link aggregation and maybe failover. The adapter would then decide which IP address (NIC) to use. This would also explain why when you disable one NIC it works thru the other fine.

I'd try looking at two things:

1.) check the application as Jefro suggested to see if there are any network configuration capabilities (for most applications that kind of iffy/doubtful), and configure it to work with one NIC, and/or

2.) check to see if you have a virtual adapters running, and how you have it configured.

I use a broadcom virtual adapter myself.

D