# -*- ispell-local-dictionary: "english" -*-

#+TITLE: Bind v9 Domain name server


* Usage

** Example =compose.yml=

#+begin_src yaml
  dns:
    charm: bind

    options:
      vars:
        ## these vars are a facility to allow using `$var` in domain defs
        myip: 1.2.3.4
      zones:
        ## __all__ will be applied to all domains defined here
        __all__:
          ns:
            ## '_' is translated to '@' in BIND v9 zone definition, which in
            ## in turn refers to the current domain being defined.
            _: (dns.mycompany.com,sdns1.ovh.net,ns6.gandi.net)
          mx:
            _: (1 ,(5 alt(1,2),10 alt(3,4)).)aspmx.l.google.com.
        mycompany.com:
          mx:
            news: 10 news

          ## Names will generate IN A/CNAME depending if an IP is detected or a name
          name:
            ## key and values can be expanded, the syntax uses the same logic
            ## than shell expansion with `{`, `}` and `,`. So this:
            ## `(_,dns,core(,-01))` will demux to `_ dns core core-01`, so all
            ## these keys will receive the following value.
            (_,dns,core(,-01)): $myip
            core-02: 4.5.6.7

          ## You can specify after a space, a TTL that will be applied to all
          ## definitions inside the section:
          name 3h:
            ## `www` required not to be an IP by zonecheck
            (www,admin,smtp,beta,alpha,erp(,-beta)): core-01
            news: 77.32.131.26
            r.news: r.mailin.fr.
            img.news: img.mailin.fr.

          spf 3h:
            ## Remember that this is YAML that also offer nice syntaxic
            ## feature to avoid repeating values.
            _: &spf >-
              v=spf1 a
              a:smtp.free.fr
              a:smtp.mycompany.com
              include:spf.sendinblue.com
              mx ?all
          txt 3h:
            _:
              - *spf
              - Sendinblue-code:xxx
              - google-site-verification=yyy

            news: "v=spf1 include:spf.sendinblue.com mx ~all"
            mail._domainkey(,.news):
              "k=rsa;p=zzz"

            _dmarc.news: >-
              v=DMARC1;
              p=none;
              sp=none;
              rua=mailto:dmarc@mailinblue.com!10m;
              ruf=mailto:dmarc@mailinblue.com!10m;
              rf=afrf;
              pct=100;
              ri=86400

        (othercompany.com,other-company.com):
          name:
            (_,www,mail): $myip
            (admin,beta): www
#+end_src


* Persistence

backup will keep:
- /etc/bind/rndc.key
- /etc/bind/.db.$DOMAIN files keeping a hash of the configuration along
  with the given serial that matches the zone file. This is to be sure to
  advertise the same serial after a recovery.