[dns-operations] IPv6 PTR records

Tony Finch dot at dotat.at
Fri Dec 24 23:39:59 UTC 2010

On 17 Dec 2010, at 19:32, Chris Adams <cmadams at hiwaay.net> wrote:
> Once upon a time, Douglas C. Stephens <stephens at ameslab.gov> said:
>> A case in point is SSHd.  Many of the other sites running
>> SSHd to which my customers connect are using versions of SSHd which
>> stall and time-out if PTR records for my client-side IPs are not
>> available.
> I've not seen that behavior from OpenSSH (or any other server for that
> matter).  It may stall if lookups don't return (e.g. bad DNS server,
> broken network, etc.), but an NXDOMAIN doesn't cause any slowdown.

Yes, the cause of the delay is more likely to be ident lookup timeouts.

f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/

More information about the dns-operations mailing list