[CentOS] SFTP - stalled - on large files

Tue Dec 22 13:06:28 UTC 2009
Sean Carolan <scarolan at gmail.com>

> Load balancer... is that set up to maintain connections, or will it, like IBM's
> WebSeal, go to whichever server is next/least used in the middle of a connection?

It's set to use "least connection" but there is only one server behind
the virtual IP at the moment.

I'm reasonably sure at this point that the Netscaler is causing the
problem, because file transfers inside the LAN work fine, and we see
this same issue on both physical and virtual servers.  I just tested
with a physical box to verify, and the same thing happens, transfer
speed quickly drops to zero and stalls.

I've got a ticket open with Citrix to hopefully get to the bottom of
this.  It wouldn't be the first time we've seen the Netscaler muck up
a TCP connection from a client.  The last time I dealt with this it
was sending unwanted FIN packets to mail servers.  Fun stuff.