Name resolution over VPN?

Hi Martinen ,

Thanks for reaching out to Sophos Community. 

To confirm, Can you ping the machines but cannot resolve hostnames? Also, by mentioning "no DNS server present in the local network" means you have no DNS on both ends (local and branch)? 

If possible, could you share your network diagram for us to better picture the setup?

Thanks,

Hi Martinen ,

Thanks for reaching out to Sophos Community. 

To confirm, Can you ping the machines but cannot resolve hostnames? Also, by mentioning "no DNS server present in the local network" means you have no DNS on both ends (local and branch)? 

If possible, could you share your network diagram for us to better picture the setup?

Thanks,

Hi Raphael,

I forgot to mention that this is remote access VPN, not site-to-site. It is set up as split-tunnel. There is only one local network, no branches. So yes, we don't have a local DNS server, name resolution is done only by public DNS servers. And yes, Ping and other services work fine as long as you know the local IPs.

Regards,
Martin

Hello Martinen ,

Could you add DNS host entry for the Windows machines you're trying to connect to? https://doc.sophos.com/nsg/sophos-firewall/20.0/help/en-us/webhelp/onlinehelp/AdministratorHelp/Network/DNS/NetworkDNSHostEntryAdd/index.html

Then, Please make sure that DNS request traverse to Sophos Firewall from the SSL VPN user system, and use SF as DNS server on the SSL VPN users DNS settings. 

On the other hand, have you tried using hostfile on the SSL VPN Machines? 

Regards,

Thanks Raphael for your suggestions,

the hosts file is a good point and I wil definitely look into the DNS host entry feature.

Thanks for your time and effort!

Kind regards,
Martin