Unbound seems to be restarting frequently

kejianshi

services > DNS resolver - unbound

services > DNS forwarder - dnsmasq

I was suggesting that you take a screen shot of the settings in there and post to see if there is anything strange there.

Or, you can post here daily "my unbound is weird" over and over…

CiscoKid85

Attached.

resolver.PNG_thumb

resolver_advanced.PNG_thumb

forwarder.PNG_thumb

system_general.PNG_thumb

kejianshi

With these settings, your unbound is just acting as a forwarder. May as well use dnsmasq instead (dns forwarder)

CiscoKid85

But I still get the benefit of pre-fetch and caching.

My actual unbound config is here.

I found the unbound logs but I'm getting permission denied when I try to view them. I also can't do a sudo or sudo su. Any suggestions on how I can get the raw logs?

I'd still like to fix unbound should I decide to not forward queries.

unbound.txt

kejianshi

Were you using unbound in 2.1.5? (yes or no)

CiscoKid85

I never used 2.1. My 2.2 build was a fresh install on a new pc engines build.

CiscoKid85

If I filter for restarts, I get the following:

Mar 2 11:52:20	unbound: [28167:0] notice: init module 0: iterator
Mar 2 11:52:20	unbound: [28167:0] notice: Restart of unbound 1.5.1.
Mar 2 10:49:14	unbound: [28167:0] notice: init module 0: iterator
Mar 2 10:49:14	unbound: [28167:0] notice: Restart of unbound 1.5.1.
Mar 2 10:49:12	unbound: [28167:0] notice: init module 0: iterator
Mar 2 10:49:12	unbound: [28167:0] notice: Restart of unbound 1.5.1.
Mar 2 10:49:12	unbound: [28167:0] notice: init module 0: iterator
Mar 2 10:09:59	unbound: [45732:0] notice: init module 0: iterator
Mar 2 10:09:59	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 10:03:14	unbound: [45732:0] notice: init module 0: iterator
Mar 2 10:03:14	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:53:20	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:53:20	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:43:24	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:43:24	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:33:30	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:33:30	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:33:30	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:33:30	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:31:00	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:31:00	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:30:56	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:30:56	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:30:20	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:30:20	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:24:02	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:24:02	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:23:29	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:23:29	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:13:34	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:13:34	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:12:04	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:12:04	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 09:09:56	unbound: [45732:0] notice: init module 0: iterator
Mar 2 09:09:56	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 08:09:43	unbound: [45732:0] notice: init module 0: iterator
Mar 2 08:09:43	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 08:02:39	unbound: [45732:0] notice: init module 0: iterator
Mar 2 08:02:39	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 07:52:44	unbound: [45732:0] notice: init module 0: iterator
Mar 2 07:52:44	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 07:49:50	unbound: [45732:0] notice: init module 0: iterator
Mar 2 07:49:50	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 07:42:49	unbound: [45732:0] notice: init module 0: iterator
Mar 2 07:42:49	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 07:40:24	unbound: [45732:0] notice: init module 0: iterator
Mar 2 07:40:24	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 07:38:15	unbound: [45732:0] notice: init module 0: iterator
Mar 2 07:38:15	unbound: [45732:0] notice: Restart of unbound 1.5.1.
Mar 2 07:37:28	unbound: [45732:0] notice: init module 0: iterator

kejianshi

Hmmmm. Is there a reason you don't want to use the root DNS servers (just curious)?

CiscoKid85

Comcast operates a bunch of caching servers for content from Akamai, Netflix. I'd like to hit the locally cached servers when that content is requested. Netflix definitely streams a little faster, I think.

kejianshi

Thing is, I think hitting the local DNS without DNSSEC and harden glue and all that might be whats crashing your unbound.

Would you be opposed to trying it in resolver mode instead of forwarder mode for a while? See if it stops crashing?

CiscoKid85

Is there any additional logging I can enable that may offer better insight?

Would someone mind posting their config so I can try running a good one that I know works?

Thanks!

CiscoKid85

How do I reset the Resolver general settings to their defaults? The GUI retains the settings from the previous config, even if I wipe out the .conf file.

hda

Why are you hard on yourself with CLI. Just use the webGUI to stop and start what you want.

Stop Services: DNS forwarder.
Clear out System: General Setup for DNS servers
Set Services: DNS Resolver(interfaces & DNSSEC) only
Services: DNS Resolver: Advanced(Harden = true)

Maybe reboot.

CiscoKid85

Disabling the forwarder and adding in the hardening both worked. I'll continue to troubleshoot w/ the forwards or perhaps just enable dnsmasq.

CiscoKid85

It seems adding DNS servers into the general settings tab causes the unbound restarts. This seems like a bug. Does anyone know how I would report this?

kejianshi

I don't know if its a bug or if something malicious is being done to your DNS… Glad its working now.

CiscoKid85

Even if it's something malicious, unbound shouldn't reboot all the time. lol

dparring

I am also seeing this issue with unbound restarting frequently on a clean 2.2 install. It is triggered by DHCPREQUEST events in dhcpd, but only when a host name is specified in the request. For example, a request to dhcpd like this:

Mar 2 15:43:41 dhcpd: DHCPREQUEST for 192.168.1.208 from xx:xx:xx:xx:xx:xx (ipcam_xxxxxxxxxxxx) via em1

…always results in a restart of unbound at the same exact time:

Mar 2 15:43:41 unbound: [55204:0] info: service stopped (unbound 1.5.1).
(followed by a bunch of info logging and then…)
Mar 2 15:43:41 unbound: [55204:0] notice: Restart of unbound 1.5.1.
Mar 2 15:43:41 unbound: [55204:0] notice: init module 0: iterator
Mar 2 15:43:41 unbound: [55204:0] info: start of service (unbound 1.5.1).

However, a DHCPREQUEST without a host name does not trigger the restart (also this is a static mapping, the one above is from the DHCP pool):

Mar 2 15:47:46 dhcpd: DHCPREQUEST for 192.168.1.11 from xx:xx:xx:xx:xx:xx via em1

I do not have "DNS Query Forwarding" enabled in the unbound configuration. After reading this thread, I tried disabling DNSSEC and it had no effect on the restarting behavior. I do have "Register DHCP leases in the DNS Resolver" and "Register DHCP static mappings in the DNS Resolver" enabled which leads me to believe the problem lies in the DHCP -> DNS registration functionality.

I would not normally notice this behavior except that there are times where the frequent restarting of unbound sometimes seems to cause unbound to stop resolving DNS queries properly. This usually happens when there are a lot of devices going on or offline and requesting DHCP leases. A manual restart of unbound in the web GUI fixes it, although the restart behavior continues whenever a DHCPREQUEST with hostname is received.

kejianshi

I think people were seeing crashes when they had devices (such as cameras or laptops) that have both a wired and wireless connection and both were connected simultaneously and shouldn't have been…

You sure you don't have something like that going on?

dparring

It is unlikely that is the case with my installation. Of the wireless devices I have on a wired connection, most don't even have the wireless SSID configured. Also, my AP and all wireless devices are on a separate subnet, so anything on the 192.168.1 subnet is 100% wired.