Re: Why sshd makes a PTR dns request after receiving user's name ?

2010-04-29 Thread Kyle Hamilton
Check /etc/pam.d/sshd and see what's being loaded. Then, look for the documentation on each of the PAM modules, and you should (if it's properly documented, which almost all PAM modules seem to be) be able to figure out which is doing the name check. You haven't stated why you're averse to this c

Re: Why sshd makes a PTR dns request after receiving user's name ?

2010-04-29 Thread barx
wolfoftheair wrote: > > The question that I'd ask, though, is "do you know which component > would do it? Is it perhaps a PAM in your system that is queried by > the sshd to perform host-based blocking?" > I don't know which component do it exactly. Is there a way other than strace to know it

Re: Why sshd makes a PTR dns request after receiving user's name ?

2010-04-28 Thread Kyle Hamilton
This is not an SSH support list. SSH uses OpenSSL libraries, but that's the extent of it. My conjecture (and this is only my conjecture): you may be running TCP wrappers, or you may have host-based access blocking disabled. In any case, it's at least used for logging purposes (since names are ea

Why sshd makes a PTR dns request after receiving user's name ?

2010-04-28 Thread barx
Hello When sshd has received the username of a linux user from a SSH client, it look likes it send a PTR request on the client's IP. for example, if 192.168.56.106 start a connection on a sshd server running on 192.168.56.1, this machine will send a PTR request on 105.56.168.192.in-addr.arpa jus