Failed to start unbound

Pluto · July 5, 2022, 1:24pm

While trying to install unbound i get error, tried to re-install & searched around with no luck

this is the error i get

sudo service unbound status
● unbound.service - Unbound DNS server
     Loaded: loaded (/lib/systemd/system/unbound.service; enabled; vendor prese>
     Active: failed (Result: exit-code) since Tue 2022-07-05 15:05:41 CEST; 4mi>
       Docs: man:unbound(8)
    Process: 22874 ExecStartPre=/usr/lib/unbound/package-helper chroot_setup (c>
    Process: 22877 ExecStartPre=/usr/lib/unbound/package-helper root_trust_anch>
    Process: 22880 ExecStart=/usr/sbin/unbound -d -p $DAEMON_OPTS (code=exited,>
    Process: 22881 ExecStopPost=/usr/lib/unbound/package-helper chroot_teardown>
   Main PID: 22880 (code=exited, status=1/FAILURE)
        CPU: 198ms

Jul 05 15:05:41 homepi systemd[1]: unbound.service: Scheduled restart job, rest>
Jul 05 15:05:41 homepi systemd[1]: Stopped Unbound DNS server.
Jul 05 15:05:41 homepi systemd[1]: unbound.service: Start request repeated too >
Jul 05 15:05:41 homepi systemd[1]: unbound.service: Failed with result 'exit-co>
Jul 05 15:05:41 homepi systemd[1]: Failed to start Unbound DNS server.

Bucking_Horn · July 5, 2022, 1:43pm

That failure may be expected - if you ran that status straight after installing unbound on a machine where Pi-hole is already present, unbound would fail because port 53 is already taken by Pi-hole.

That would be curable by adopting unbound's configuration for a different port.
For having unbound work in collaboration with Pi-hole, see e.g. unbound - Pi-hole documentation.

jfb · July 5, 2022, 1:44pm

Please post the output of the following command from the Pi terminal:

sudo grep -v ‘#\|^$’ -R /etc/unbound/unbound.conf*

Pluto · July 5, 2022, 1:52pm

this worked, but during following the instruction, the first one should be SERVFAIL and the second NOERROR, but in both cases i get SERVFAIL is this normal

Bucking_Horn · July 5, 2022, 2:29pm

Please provide the results as well as the commands that produced them exactly as you've run them, and please also comply with jfb's earlier request.

Pluto · July 5, 2022, 2:38pm

pi@homepi:~ $ sudo grep -v ‘#\|^$’ -R /etc/unbound/unbound.conf*
/etc/unbound/unbound.conf:# Unbound configuration file for Debian.
/etc/unbound/unbound.conf:#
/etc/unbound/unbound.conf:# See the unbound.conf(5) man page.
/etc/unbound/unbound.conf:#
/etc/unbound/unbound.conf:# See /usr/share/doc/unbound/examples/unbound.conf for a commented
/etc/unbound/unbound.conf:# reference config file.
/etc/unbound/unbound.conf:#
/etc/unbound/unbound.conf:# The following line includes additional configuration files from the
/etc/unbound/unbound.conf:# /etc/unbound/unbound.conf.d directory.
/etc/unbound/unbound.conf:include-toplevel: "/etc/unbound/unbound.conf.d/*.conf"
/etc/unbound/unbound.conf.d/root-auto-trust-anchor-file.conf:server:
/etc/unbound/unbound.conf.d/root-auto-trust-anchor-file.conf:    # The following line will configure unbound to perform cryptographic
/etc/unbound/unbound.conf.d/root-auto-trust-anchor-file.conf:    # DNSSEC validation using the root trust anchor.
/etc/unbound/unbound.conf.d/root-auto-trust-anchor-file.conf:    auto-trust-anchor-file: "/var/lib/unbound/root.key"
/etc/unbound/unbound.conf.d/resolvconf_resolvers.conf:# Generated by resolvconf
/etc/unbound/unbound.conf.d/resolvconf_resolvers.conf:
/etc/unbound/unbound.conf.d/resolvconf_resolvers.conf:forward-zone:
/etc/unbound/unbound.conf.d/resolvconf_resolvers.conf:	name: "."
/etc/unbound/unbound.conf.d/resolvconf_resolvers.conf:	forward-addr: fdf7:e7d9:6000::1
/etc/unbound/unbound.conf.d/pi-hole.conf:server:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # If no logfile is specified, syslog is used
/etc/unbound/unbound.conf.d/pi-hole.conf:    # logfile: "/var/log/unbound/unbound.log"
/etc/unbound/unbound.conf.d/pi-hole.conf:    verbosity: 0
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    interface: 127.0.0.1
/etc/unbound/unbound.conf.d/pi-hole.conf:    port: 5335
/etc/unbound/unbound.conf.d/pi-hole.conf:    do-ip4: yes
/etc/unbound/unbound.conf.d/pi-hole.conf:    do-udp: yes
/etc/unbound/unbound.conf.d/pi-hole.conf:    do-tcp: yes
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # May be set to yes if you have IPv6 connectivity
/etc/unbound/unbound.conf.d/pi-hole.conf:    do-ip6: no
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # You want to leave this to no unless you have *native* IPv6. With 6to4 and
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Terredo tunnels your web browser should favor IPv4 for the same reasons
/etc/unbound/unbound.conf.d/pi-hole.conf:    prefer-ip6: no
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Use this only when you downloaded the list of primary root servers!
/etc/unbound/unbound.conf.d/pi-hole.conf:    # If you use the default dns-root-data package, unbound will find it automatically
/etc/unbound/unbound.conf.d/pi-hole.conf:    #root-hints: "/var/lib/unbound/root.hints"
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Trust glue only if it is within the server's authority
/etc/unbound/unbound.conf.d/pi-hole.conf:    harden-glue: yes
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Require DNSSEC data for trust-anchored zones, if such data is absent, the zone becomes BOGUS
/etc/unbound/unbound.conf.d/pi-hole.conf:    harden-dnssec-stripped: yes
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Don't use Capitalization randomization as it known to cause DNSSEC issues sometimes
/etc/unbound/unbound.conf.d/pi-hole.conf:    # see https://discourse.pi-hole.net/t/unbound-stubby-or-dnscrypt-proxy/9378 for further details
/etc/unbound/unbound.conf.d/pi-hole.conf:    use-caps-for-id: no
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Reduce EDNS reassembly buffer size.
/etc/unbound/unbound.conf.d/pi-hole.conf:    # IP fragmentation is unreliable on the Internet today, and can cause
/etc/unbound/unbound.conf.d/pi-hole.conf:    # transmission failures when large DNS messages are sent via UDP. Even
/etc/unbound/unbound.conf.d/pi-hole.conf:    # when fragmentation does work, it may not be secure; it is theoretically
/etc/unbound/unbound.conf.d/pi-hole.conf:    # possible to spoof parts of a fragmented DNS message, without easy
/etc/unbound/unbound.conf.d/pi-hole.conf:    # detection at the receiving end. Recently, there was an excellent study
/etc/unbound/unbound.conf.d/pi-hole.conf:    # >>> Defragmenting DNS - Determining the optimal maximum UDP response size for DNS <<<
/etc/unbound/unbound.conf.d/pi-hole.conf:    # by Axel Koolhaas, and Tjeerd Slokker (https://indico.dns-oarc.net/event/36/contributions/776/)
/etc/unbound/unbound.conf.d/pi-hole.conf:    # in collaboration with NLnet Labs explored DNS using real world data from the
/etc/unbound/unbound.conf.d/pi-hole.conf:    # the RIPE Atlas probes and the researchers suggested different values for
/etc/unbound/unbound.conf.d/pi-hole.conf:    # IPv4 and IPv6 and in different scenarios. They advise that servers should
/etc/unbound/unbound.conf.d/pi-hole.conf:    # be configured to limit DNS messages sent over UDP to a size that will not
/etc/unbound/unbound.conf.d/pi-hole.conf:    # trigger fragmentation on typical network links. DNS servers can switch
/etc/unbound/unbound.conf.d/pi-hole.conf:    # from UDP to TCP when a DNS response is too big to fit in this limited
/etc/unbound/unbound.conf.d/pi-hole.conf:    # buffer size. This value has also been suggested in DNS Flag Day 2020.
/etc/unbound/unbound.conf.d/pi-hole.conf:    edns-buffer-size: 1232
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Perform prefetching of close to expired message cache entries
/etc/unbound/unbound.conf.d/pi-hole.conf:    # This only applies to domains that have been frequently queried
/etc/unbound/unbound.conf.d/pi-hole.conf:    prefetch: yes
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # One thread should be sufficient, can be increased on beefy machines. In reality for most users running on small networks or on a single machine, it should be unnecessary to seek performance enhancement by increasing num-threads above 1.
/etc/unbound/unbound.conf.d/pi-hole.conf:    num-threads: 1
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Ensure kernel buffer is large enough to not lose messages in traffic spikes
/etc/unbound/unbound.conf.d/pi-hole.conf:    so-rcvbuf: 1m
/etc/unbound/unbound.conf.d/pi-hole.conf:
/etc/unbound/unbound.conf.d/pi-hole.conf:    # Ensure privacy of local IP ranges
/etc/unbound/unbound.conf.d/pi-hole.conf:    private-address: 192.168.0.0/16
/etc/unbound/unbound.conf.d/pi-hole.conf:    private-address: 169.254.0.0/16
/etc/unbound/unbound.conf.d/pi-hole.conf:    private-address: 172.16.0.0/12
/etc/unbound/unbound.conf.d/pi-hole.conf:    private-address: 10.0.0.0/8
/etc/unbound/unbound.conf.d/pi-hole.conf:    private-address: fd00::/8
/etc/unbound/unbound.conf.d/pi-hole.conf:    private-address: fe80::/10

Pluto · July 5, 2022, 2:42pm

i am trying this step

Test validation¶

You can test DNSSEC validation using

dig sigfail.verteiltesysteme.net @127.0.0.1 -p 5335
dig sigok.verteiltesysteme.net @127.0.0.1 -p 5335

The first command should give a status report of SERVFAIL and no IP address. The second should give NOERROR plus an IP address.

this is my result below

dig sigfail.verteiltesysteme.net @127.0.0.1 -p 5335
dig sigok.verteiltesysteme.net @127.0.0.1 -p 5335

; <<>> DiG 9.16.27-Raspbian <<>> sigfail.verteiltesysteme.net @127.0.0.1 -p 5335
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 42733
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;sigfail.verteiltesysteme.net.	IN	A

;; Query time: 0 msec
;; SERVER: 127.0.0.1#5335(127.0.0.1)
;; WHEN: Tue Jul 05 15:47:39 CEST 2022
;; MSG SIZE  rcvd: 57


; <<>> DiG 9.16.27-Raspbian <<>> sigok.verteiltesysteme.net @127.0.0.1 -p 5335
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 64239
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;sigok.verteiltesysteme.net.	IN	A

;; Query time: 0 msec
;; SERVER: 127.0.0.1#5335(127.0.0.1)
;; WHEN: Tue Jul 05 15:47:39 CEST 2022
;; MSG SIZE  rcvd: 55

pi@homepi:~ $ dig sigfail.verteiltesysteme.net @127.0.0.1 -p 5335

; <<>> DiG 9.16.27-Raspbian <<>> sigfail.verteiltesysteme.net @127.0.0.1 -p 5335
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 13579
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;sigfail.verteiltesysteme.net.	IN	A

;; Query time: 0 msec
;; SERVER: 127.0.0.1#5335(127.0.0.1)
;; WHEN: Tue Jul 05 15:48:28 CEST 2022
;; MSG SIZE  rcvd: 57

jfb · July 5, 2022, 3:06pm

Edit file /etc/resolvconf.conf and comment out the last line which should then read:

#unbound_conf=/etc/unbound/unbound.conf.d/resolvconf_resolvers.conf

Delete the unwanted unbound configuration file:

sudo rm /etc/unbound/unbound.conf.d/resolvconf_resolvers.conf

Restart unbound:

sudo service unbound restart

Pluto · July 5, 2022, 5:10pm

everything is working as it should thanks for the help @jfb @Bucking_Horn.

just curious how do i know that the pihole-unbound are working, when i check dnsleaktest i see that i'm using my ISP's DNS ?

jfb · July 5, 2022, 6:34pm

You are likely seeing the IP of your modem or ISP. This is normal with unbound in recursive mode - your DNS server is running at your home IP.