DNS issues demystified

[Predrag Punosevac]

Dear Autonians,

I got to the bottom of DNS/OpenVPN issue. As I suspected the CMU network
guys have being upgrading backplane on the switches.  The CMU switches
are now passing packets at the speeds of 20 Gigabit/s.

Best,
Predrag

Predrag Punosevac <predragp at imap.srv.cs.cmu.edu> wrote:

> On 2017-04-27 11:48, Simon Heath wrote:
> > Dear all,
> > 
> > Several people are experiencing intermittent DNS issues.  We are
> > looking into it and will follow up when we figure out what's going on.
> > 
> > Simon
> > 
> 
> DNS issue on desktops seems to be resolved at this point.I restarted 
> OpenVPN
> server which also serves as the DNS resolver for desktops. It is not 
> clear
> to me (even after going through log files) what caused the problem 
> (OpenVPN
> connection between desktops and the main firewall/OpenVPN server being a 
> prime suspect).
> People who were trying to access computing nodes from the 
> lop1.autonlab.org
> never experienced any problems which is another pointer to OpenVPN 
> server.
> 
> I did physically inspect the server and made sure that cables OK. I was 
> unable
> to locate Matt Nickelson (CS CMU network guy) which is kind a bad sign 
> as
> he had lots issues yesterday with his switches. I am continue to monitor 
> the situation
> and I am ready to act.
> 
> Best,
> Predrag
> 
> > --
> > 
> >  Simon Heath, Research Programmer and Analyst
> > Robotics Institute - Auton Lab
> > Carnegie Mellon University
> > sheath at andrew.cmu.edu