Re: Problem with slow and nonreliable IPSec tunnel

Lee Sharp <[email protected]> Thu, 30 May 2013 19:31:38 -0500
Newsgroups gmane.comp.security.firewalls.m0n0wall
Message-ID <[email protected]>
On 05/30/2013 07:15 PM, Ludvik Roubicek wrote:
> The CPU usage is approx 15-20% on both of them when copying the 200MB
> ISO image thru the tunnel. Speed is about 280kB/s.
> But when I connect using PPTP to each single node and upload/download
> from/to my desktop to/from respective PC the speed is about 1MB/s
> (outside the rush hours).
> It seems like network problem somewhere between their 2 sites or some
> bad configuration.

See if you can set the MTU on both firewalls to 1300.  I know this 
sounds odd, but it is a way to eliminate that issue.  You may have to 
manually set this if you are not running pppoe.  Go to Diagnostics, 
Backup/Restore (/diag_backup.php). Download
your config. Open it with a text editor that understand CR/LF issues and 
under <interfaces><wan> insert <mtu>1300</mtu>.