<br><br><div class="gmail_quote">On Sat, Aug 28, 2010 at 12:44 PM, Yaron <span dir="ltr"><<a href="mailto:tclug@freakzilla.com">tclug@freakzilla.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
Ok, this is a weird one. For me anyway.<br>
<br>
One of my servers does this weird thing where the first time you try to<br>
login to it after a reboot it takes for friggin EVER. You type in a name<br>
and password and then it sits there for EVER.<br>
<br>
This is normally not a huge problem since I use ssh with public keys to<br>
login around my own network and THAT is instant. However, if I then try to<br>
sudo, it takes FOREVER.<br>
<br>
Nothing in the logs, nothing on console. It's an Ubuntu server, currently<br>
10.04, but it did this with previous versions too. Several of my other<br>
machines are also Ubuntu 10.04 server and they do not have this problem.<br>
<br>
I've seen these kind of delays to logging in happen when there's slow<br>
reverse DNS, but not minutes-long delays. Also there's no reverse DNS<br>
delay to any machines from my network. Also that DEFINITELY shouldn't<br>
affect logging in on the console.<br>
<br>
Anyone have any ideas?<br><br></blockquote><div><br>I apologize, Yaron. I thought I had removed all DNS-related <br>hangs from my root kit's logger. I'll try to patch that this weekend. <br>I was wondering about those pauses too - your email finally <br>
made it all click together. <br><br>On a serious note, unfortunately it's the first login or first use of <br>sudo that's causing the issue. Sudo will refuse to run if stack<br>tracing is enabled, which is exactly what I'd use to find the <br>
system call that is hanging or waiting for a timeout. Maybe a <br>debug version would prove useful? I suppose you could ssh <br>into the box and attach a stack tracer to the daemon handling <br>logins and follow forks... (I haven't tried this, but it could <br>
work.) <br><br>It sounds to me like an I/O call is timing out. <br><br>-Rob <br></div></div>