Unbound (1.9)

I use unbound largely out of a habit to try different things. Your mileage will vary.

If using DNSSec, you'll want to make an /etc/unbound/dnssec/ directory (or something similar) and have unbound own it.

• You may want to make this a tmpfs partition.
• In addition to unbound you probably want dnsutils, and possibly rblcheck depending on your needs.

/etc/unbound/unbound.conf

1. I start by copying over the sample configuration file. It's a decent starting point.
2. Since I'm not using this for a major DNS server (it will never serve an external request), I set threads to 2.
3. Set localhost and private interfaces
4. Outgoing interfaces as appropriate - especially for IPv6
5. Restrict ports to a smallish (~8k) range
   1. Largely so you know you have a safe range for other services.
6. Be sure to add bound ipv6 addresses to /etc/network/interfaces - AnyIP only binds inbound.
7. Don't forget access-control
8. qname minimisation: yes
9. I set most cache sizes to 32m - you'll want a lot more for more important servers, however.
10. Turn on prefetching for results and keys.
11. control-enable: no under remote-control:
12. do-deamonize: no (since we're under systemd now)

For DNSSEC:

1. auto-trust-anchor-file: "/etc/unbound/dnssec/root.key"

/etc/apparmor.d/usr.sbin.unbound

Change

• owner /etc/unbound/*.key* rw,

To:

• owner /etc/unbound/dnssec/*.key* rw,

Then

systemctl restart apparmor

/etc/cron.daily/unbound-anchor

Update the root key for DNSSec

#!/bin/sh
#/etc/cron.daily/unbound-anchor
if [ -f /usr/sbin/unbound-anchor ]; then
    /usr/sbin/unbound-anchor -a /etc/unbound/dnssec/root.key
fi

/etc/resolv.conf

Set this up so we actually query ourselves!

# Unless we're dealing with an intranet of some sort, set search to some nonsense tld.
search invalid
# Default timeout is 5, have had some issues with 1.
options timeout:3
nameserver ::1
nameserver host.or.google.here
nameserver host.or.google.here

watchdog.unbound.sh

Unbound sometimes chokes on me, if rarely, and my members then complain about not getting their notifications immediately. I wrote a watchdog script to take care of this:

#!/bin/sh
run=`ps ax | grep "/usr/sbin/unbound" | grep -v grep | cut -c1-5 | paste -s -`
if [ "$run" ];
  then
    continue
  else
    /usr/bin/systemctl start unbound
fi

And for /etc/cron.d/watchdog (or whatever)

*/2     *       *       *       *       root       /root/watchdog.unbound.sh

If that's where you put your watchdog script. I'm lazy.

Debian Buster

Initial: Designing a Server - IPMI Installation - Second Steps

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Core: Network - OpenSSH - Packages - sysctl.conf - Iptables - Security - User Management

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Stack: Unbound - MariaDB - Nginx - PHP (7)

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Mail

Mail Setup - Mail Tables - OpenDKIM - Mail and DNS - Spamassassin - ClamAV - Postfix - Dovecot - Reputation Management

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Logs and Security: RKHunter - Logging - Logcheck - Backups - AppArmor