Sudden onset ftp problem - can't ftp through vpn

[Bill Oliver]

On Wed, 2 Jul 2014, Rick Stevens wrote:

>
> I hit a similar thing on my F19 machine. The fix I had was (as root):
>
> 	echo "0" >/proc/sys/net/ipv4/tcp_sack
>
> (I did this on the advice of our in-house network guru) I then added
> these to the end of my /etc/sysctl.conf file so it gets set on the next
> boot as well:
>
> 	 # Speed up FTP uploads...
> 	 net.ipv4.tcp_sack = 0
>
> Seems to have solved the problem. It appears that there are some routers
> or firewalls or VPNs that screw up the SACK on some transactions. Try
> the first thing (the echo command) and see if it helps. If so, then do
> the sysctl.conf stuff.

No joy.  I have a support call into my virtual machine vendor.  I'll see
if they have any words of wisdom.


billo