Sonicwall firewall blocking isakamp of competing product's..

Archived from groups: comp.security.firewalls (More info?)

"arabub" <arabub@yahoo.com> wrote in message
news:a714a1f2.0406092010.72f8af67@posting.google.com...
> Lots of our users can connect to our Astaro VPN gateway ("gateway" )
> from workstations that are located behind firewalls that perform PAT.
> We are using SSH's Sentinel VPN client, using isakamp/IPSEC.
>
> There is one user who can successfully connect from her laptop when at
> home where she has a consumer grade firewall. When she is at work,
> however, where she is behind a SonicWall firewall, she cannot connect
> to our gateway.
>
> I looked at the traffic that arrives at the gateway when a VPN is
> initiated, by running tcpdump on the Astaro VPN gateway, and found
> that there is absolutely no traffic arriving at the gateway when she
> tries to establish a VPN from behind the SonicWall firewall!
>
> Is this a known problem ("feature" ) of the SonicWall?
> Could it be that SonicWall filters out isakamp packets?
>
> Thanks,
> --Ulf

I believe the SonicWALL firewall is configured (by default) to block UDP
port 500. To add it to the policy should be rather easy as it's
predefined as 'Key Exchange (IKE)'.

--
Best regards, from Don Kelloway of Commodon Communications
Visit http://www.commodon.com to learn about the "Threats to Your
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