SystemAdministration/TheHitchhikersGuideToTheli694-22Domain

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In many of the more relaxed civilizations of Linode, the Hitchhiker's Guide has already supplanted the great Encyclopaedia Galactica as the standard repository of all knowledge and wisdom, for though it has many omissions and contains much that is apocryphal, or at least wildly inaccurate, it scores over the older, more pedestrian work in two important respects.

Common Information

All nodes are present on the Dallas, TX Linode Datacenter, and have static IPs. From within the nodes themselves, we have a local DNS allowing them to refer to each other under the li694-22 TLD (a reference to our original pre-launch URL).

  • All nodes support kerberos authetication to allow node-for-node access
  • shell access is only allowed from desiginated nodes.
  • LDAP and Kerberos is available on all nodes unless noted
  • sysops can access all nodes, they are not explicately listed below
Node Name Public Addresses Who Can Acces (POSIX groups) Is Running What
hydrogen soylentnews.org prod_access slashd, varnish, apache 1.3, nginx
helium None db mysql (prod master)

ldap (master) Kerberos KDC (master) BIND (master, li694-22 zone)

beryllium wiki.soylentnews.org svcadmin A lot of stuff, mechanicjay, fill me in?
  • This node is not LDAPed or KRB5ed, needs its own username/passwords
lithium dev.soylentnews.org dev_team slashd, varnish, apache 1.3, nginx, mysql (dev DB)
boron {staff,status}.soylentnews.org firefighters apache 2.2 (userdir)

KDC slave DNS slave for li694-22 LDAP slave (not fully setup)

carbon irc.soylentnews.org ircops IRC server, services & httpd

Naming Scheme

Nodes are named after the periodic table of elements, which should keep us good for a long while. Keep going up in order until we finally run out.

DNS Setup

important: The DNS zones are nicely formatted, please try to keep it that way, also do NOT forget to update the zone file's serial if you've updated a zone.

As described earlier, we're using the li694-22 TLD internally which is represented by the following name servers 'helium.li694-22' (master) and 'boron.li694-22' (slave), we're currently serving two zones, firstly the 'li694-22.' zone and secondly the reverse zone '168.192.in-addr.arpa.'.

Both servers have configuration files in the same location: /etc/bind/. Note: The master also keeps it's zone files in this directory. The slave however, keeps zone files in /var/cache/bind/.

The zone files are called: 'db.li694-22' and 'db.192-rev'.

The li694-22 zone has an A-record for every node name (e.g. Carbon), it also lists public IPs (A and AAAA) for nodes (if any), for instance, carbon:

; Carbon (IRC)
carbon          IN      A               [redacted]
pub.carbon      IN      A               50.116.18.95
pub.carbon      IN      AAAA            2600:3c00::f03c:91ff:fe6e:c4b8

As an addition, most nodes have aliases which are CNAMEs for the node's name, and each alias also has a 'pub.<alias>' which in turn is a CNAME for pub.node_name, for example:

irc             IN      CNAME           carbon
pub.irc         IN      CNAME           pub.carbon

The reverse zone, has entries that look like:

[redacted]      IN      PTR             carbon.li694-22.

If you like to add a reverse DNS entry, do the following from the command line (example IP = 192.168.136.231):

[22:21] xlefay@carbon $ host 192.168.136.233
Host 233.136.168.192.in-addr.arpa. not found: 3(NXDOMAIN)

You'll now see the 233.136.168.192.in-addr.arpa. part, grab the first two segments and add those in the zone file at the bottom like so:

233.136 IN PTR nodename.li694-22.