Underscores in Hostname

[loopforever]

Hi John,

I recently had a problem with a reseller with their own nameservers. After a named update, the service was restarted and his particular domain failed to load, all kinds of nslookup funniness. Once I looked at his zone file, I saw the issue: an underscore in a hostname of an A record.

named won't complain on restart, but all records following the _ do not get interpreted.

I removed the A record containing the _, restarted named, problem solved.

Not sure if anyone else has had this problem (running DA 1.32.0) - but records containing _ should not be permitted via the DNS forms on the panel.

Hope all is well with you guys! Talk to you later!

 

[nobaloney]

Since users shouldn't be able to register domain names with underscores in them (see RFC 952), no one should have a domain name with an underscore in it.

Because of the relatively recent introduction of international characters into domain names it's probably best that DirectAdmin allows all characters; placing limits might be a bit complex.

However, since using an underscore can actually break DNS, perhaps making a special exception to disallow an underscore, it might be an important exception.

Let's see what DirectAdmin staff think.

Jeff

 

[DirectAdmin Support]

Ok, I've added a check for underscores. So they will be denied for everything except TXT and SRV records.... which I believe is where they are still allowed.

If anyone see's any cases where underscores should be allowed in anything other than TXT and SRV records, let me know. I know that things like domain keys in TXT records need underscores.

John

 

[nobaloney]

The original post in this thread was a request to allow underscores in hostnames. Where they're not supposed to be allowed. But where people could be using them.

Jeff