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I want to create PTR record in my dns records using ispconfig. It asks me 2 values:

  1. Name
  2. Canonical Hostname
  3. TTL (default: 86400)

How should I fill these values? What do they mean?

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Not really sure what this looks like in ISPconfig. But normally in the "Name" box you would fill in the IP you want to have resolve, and in "Canonical Hostname" the hostname this should resolve to. edit TTL = Time To Live which tells the resolving name server (the client) how long this record is valid for. That is used for DNS Caching. –  Flash Nov 16 '12 at 9:23
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1 Answer

A PTR record is just the reverse of a [forward] DNS record. Although DNS has the specific PTR record type for this, zone files for those records are a bit of a kludge. I'm not sure about ISPCONFIG, but below is what you need to know.

If you have a [forward] DNS record www.example.com. A 1.2.3.4, then the reverse PTR record typically would be 4 PTR www.example.com where 4 is the last octect of the IP address.

Now this only makes sense if the PTR record is in a specially name zone file called 3.2.1.in-addr.arpa. Again, hopefully you're not having to deal with this, but thought you should be aware.

You mentioned 2 values, but listed 3. For a PTR record, the first would be an part of the IP address, not a name per se. The CName is the forward DNS name like www.example.com. The TTL is the cache duration is seconds with 86400 being 1 day or 24 hours.

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