Resolving DNS example

Content DNS server example file

This data file is an example of one which can be uploaded through our content DNS service.

You can put all your domains’ data in one file or (as we tend to do) put one file per domain, with extra files for automatically generated DNS fragments; how you organise and maintain the files is up to you.

Note that this is the tinydns-data format with IPv6 extensions, which you may be familiar with already.

# tinydns data fragment for example.com domain -- this file is for illustrative purposes only and any records ending in example.com will be ignored. You should adapt it for your own domains. The latest example file will be kept at https://www.bytemark.co.uk/dnsc

# As you may have noticed, lines beginning with hash characters and blank lines are ignored, and can be safely deleted.

# tinydns record lines start with a single character describing the record type, followed by a colon-separated list of fields.

# Full reference is at <a href="http://cr.yp.to/djbdns/tinydns-data.html">http://cr.yp.to/djbdns/tinydns-data.html</a> Brief notes on the IPv6 support can be found at <a href="http://www.fefe.de/dns/">http://www.fefe.de/dns/</a>

# Assuming you have delegated to a.ns.bytemark.co.uk, b.ns.bytemark.co.uk and c.ns.bytemark.co.uk as recommended by us, you need to insert these three lines for each domain.

.example.com::a.ns.bytemark.co.uk
.example.com::b.ns.bytemark.co.uk
.example.com::c.ns.bytemark.co.uk

# This is an MX (mail exchanger) record, declaring the IP address 1.2.3.4 to receive mail for example.com. This means that when an email program sends mail to example.com it will expect this addresses to have an SMTP server listening and happy to receive mail for addresses ending in @example.com

# The penultimate field is the "MX distance".

@example.com:1.2.3.4:a:10

# This is an alias record, saying that www.example.com points to IP address 1.2.3.4

+www.example.com:1.2.3.4

# This is a set of alias records for www.popularsite.example.com -- the DNS server will respond with all of these IP addresses if asked for www.popularsite.example.com , and the client will ask one of them randomly.

+www.popularsite.example.com:1.2.3.20
+www.popularsite.example.com:1.2.3.21
+www.popularsite.example.com:1.2.3.22

# This is a wildcard alias record-- it tells tinydns to provide the mapping of 1.2.3.4 to any request ending in wild.example.com that doesn't have a more specific record matching it, so xyz.wild.example.com will return 1.2.3.4, as will abc.wild.example.com but exceptionto.wild.example.com will return 1.2.3.5 since it is more specific.

+*.wild.example.com:1.2.3.4
+exceptionto.wild.example.com:1.2.3.5

# This is a host record, saying that mymachine.example.com is the IP address 1.2.3.4. It also inserts a corresponding reverse DNS record saying that the address 1.2.3.4 has the name mymachine.example.com -- hence you should only have one of these entries for each IP address.

=mymachine.example.com:1.2.3.4

# This is a delegation record, saying that servers 1.2.3.8 and 1.2.3.9 will know about any DNS records ending with sub.domain.example.com. You should set up those IPs to serve "." records (see above) to claim authority for the delegated domain.

# &amp;sub.domain.example.com:1.2.3.8:a
# &amp;sub.domain.example.com:1.2.3.9:b

# These are IPv6 reverse DNS authority records. This tells the outside world that Bytemark's name servers are authoritative for reverse DNS looks for the IP range 2001:41c8:1:4e24:/64. This is the default delegation for IPv6 blocks allocated to Bytemark customers, but can be changed if you would prefer not to use our servers.

# .4.2.e.4.1.0.0.0.8.c.1.4.1.0.0.2.ip6.arpa::a.ns.bytemark.co.uk
# .4.2.e.4.1.0.0.0.8.c.1.4.1.0.0.2.ip6.arpa::b.ns.bytemark.co.uk
# .4.2.e.4.1.0.0.0.8.c.1.4.1.0.0.2.ip6.arpa::c.ns.bytemark.co.uk

# This is an IPv6 record stating that the name sixconnection.example.com should point to the IPv6 address 2001:41c8:1:4e24::2. Note that you need to quote the IPv6 address in full without colon separators. This will also insert a suitable DNS record (though see above, you must have claimed authority for the reverse DNS block before the reverse DNS will work).

# 6sixconnection.example.com:200141c800014e240000000000000002

# This is an IPv6 alias record. This works the same as above but does not insert a reverse DNS record, for situations where you are not the "owner" of the IP that you are pointing to, or where you have already declared a 6 record for the same IP.

# 3www.example.com:200141c800014e240000000000000002

# This is a record delegating the reverse DNS for 2001:41c8:1:4e24::/64 to the IPv4 addresses 1.2.3.8 and 1.2.3.9. Those IPs should then run DNS servers answering for the reverse DNS domain.

# &amp;0.0.0.0.0.0.0.0.0.0.0.0.4.2.e.4.1.0.0.0.8.c.1.4.1.0.0.2.ip6.arpa:1.2.3.8:a
# &amp;0.0.0.0.0.0.0.0.0.0.0.0.4.2.e.4.1.0.0.0.8.c.1.4.1.0.0.2.ip6.arpa:1.2.3.9:b
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