topic Re: DNS stops resolving name in Remote Access VPN in SASE and Remote Access

DNS stops resolving name in Remote Access VPN

Di_Junior — Tue, 18 Dec 2018 12:43:44 GMT

Dear Mates

I have currently migrated our Remote Access VPN to Check Point, and everything seems to be working. However, from time to time, there is a problem with DNS resolving the names. when this happens, it displays the message in the photo bellow. Since I dont know the cause of the problem, sometimes a workaround that I found is to push the policy again on the firewall where the RA is terminated, and then it works just fine.

Any idea on what could be causing this, and how it can be resolved?

Thanks in advance

Re: DNS stops resolving name in Remote Access VPN

ED — Tue, 18 Dec 2018 13:51:34 GMT

Hi,

I had recently the same problem with DNS for another situation. In my case it was problem with the "forwarders" for the DNS server itself. Also the Server: unknown information is related to the "Reverse lookup zone" for your DNS-server. (if you don't have a reverse lookup for your DNS server).

Re: DNS stops resolving name in Remote Access VPN

Di_Junior — Tue, 18 Dec 2018 13:55:36 GMT

HI Enis,

Thanks for your help.

But how do I fix this problem once and for all.

Regards

Re: DNS stops resolving name in Remote Access VPN

PhoneBoy — Wed, 19 Dec 2018 00:08:32 GMT

Recommend a TAC case for this issue.

Re: DNS stops resolving name in Remote Access VPN

ED — Wed, 19 Dec 2018 07:14:32 GMT

May I ask if you are using Windows server for DNS so that I can try to explain what I meant?

Re: DNS stops resolving name in Remote Access VPN

Di_Junior — Wed, 19 Dec 2018 08:20:12 GMT

Hi Enic

Yes, we are using Windows Server for DNS.

Re: DNS stops resolving name in Remote Access VPN

ED — Wed, 19 Dec 2018 09:42:12 GMT

Open up DNS manager. On top select your DNS server, right-click and select Properties. On the new window select "Forwarders" tab. Do you have anything there? You can try to use forexample 8.8.8.8 (Google) or 1.1.1.1 (Cloudflare).

Also check in DNS manager if you have reverse lookup zone for your domain.

Re: DNS stops resolving name in Remote Access VPN

Scott_White — Fri, 08 May 2020 18:23:01 GMT

We have been experiencing this issue sporadically as well. We have noticed that nearly all of the users experiencing the issue are using Comcast for their ISP.

Checkpoint FW verison
- Product version Check Point Gaia R80.20
- OS build 101
- OS kernel version 2.6.18-92cpx86_64
- OS edition 64-bit
- Checkpoint VPN CLient Version:
  - VPN E80.62 Build 986000452
  - Other Versions as well
  - OS:
    Windows 10
    Windows 7

Re: DNS stops resolving name in Remote Access VPN

scenarist — Fri, 05 Jul 2024 07:19:45 GMT

I have the same problem. I set everything according to the procedure for using internal DNS servers.

When I connect to remote VPN I have my internal dns in checkpoint virtual adapter but when run nslookup.

I also checked reverse lookup zones and it exists.