FTP over IPsec

shailendra.singh · ‎03-01-2008

Dear All,

I am facing a slow response issue when using FTP over IPSec tunnel between Branch office Router and CO router

If I do FTP without IPsec then it works fine.

Please suggest.

Thanks,

Shailendra

Joseph W. Doherty · ‎03-02-2008

Possibly due to reduction of MTU when FTP is encapsulated within IPSec. If able, and if not already doing so, might try "ip tcp adjust-mss" with appropriate value to avoid fragmentation.

DenversCC · ‎07-15-2013

Could you please explain how to do this, I am having the same problem between two Cisco RV220W's. FTP over my VPN is so slow, that I have to slow down the FTP Transfer to about 10kbps in order to keep the tansfer steady. Trying to move TB's of information at that speed is not reasonable.

Marvin Rhoads · ‎07-15-2013

There are a couple of good articles on the details of why this is often advisable on VPN-based links.

Cisco article

Packetlife article

Both are pretty old but the underlying technology is even older.

The basic setting is an interface configuration mode setting as follows:

int

ip tcp adjust-mss 1460