OPNsense Forum

English Forums => General Discussion => Topic started by: gintek on September 09, 2021, 12:31:03 AM

Title: [Resolved] Baffling DNS issue - can't access sites until 10-15 mins after reboot
Post by: gintek on September 09, 2021, 12:31:03 AM
Over the weekend I got OpnSense set up for the first time, and I'm loving it.

That said, I'm hitting an issue that has me completely perplexed. For some reason, I can't access anything that requires DNS translation for roughly the first 10-15 minutes after a reboot. I can ping external IPs and can directly access hosts on my LAN via IP. I'm hoping that someone else may have run into this before, and has some recommendations for things I can try to resolve it.

Here are a few notes that may be worth mentioning:

Thanks in advance for any help troubleshooting this!
Title: Re: Baffling DNS issue - can't access any sites until 10-15 mins after reboot
Post by: cookiemonster on September 09, 2021, 11:42:59 PM
I doubt is the setup. As it is, it works but with that long delay.
Assuming OPN is the upstream resolver for AdGuard then that leaves you with a timing issue to track.
The name resolution from ADG is down during OPN's reboot and this time can be a few minutes based on hardware. 15 minutes sounds long for a reboot.
That makes me think you could try letting OPN do name resolution bypassing ADG for a test.
If that reduces considerably, you can narrow things down.
Title: Re: Baffling DNS issue - can't access any sites until 10-15 mins after reboot
Post by: gintek on September 13, 2021, 07:31:04 AM
Thanks a lot for the help, cookiemonster! I took your advice, and reconfigured things so that OpnSense could go directly out to the DNS server, bypassing AdGuard Home. Upon reboot, as suspected, it worked immediately.

Out of curiosity, I figured it as good of an excuse as any to just take a shot at activating the AdGuard plug-in and Unbound, to see if I could get it all going. I had a bit of trouble with the firewall rule recommended in this post (https://forum.opnsense.org/index.php?topic=22162.0), but once I disabled that, things are now working immediately after reboots.

I'm still left wondering what the issue could have been between OpnSense and the RPi instance of AGH, but I'm happy with it as is, so will let sleeping dogs lie. :D Not to mention, now I've got an extra Pi0 to have some new fun with.

Thanks again for your help!