Quartus / Ubuntu DNS problem and solution

[Altera_Forum]

I recently experienced an unusual sudden crash with Quartus. 

 Quartus v8.0 was completely operational on Ubuntu v8.04 until we had a simple DNS server host change... after the host change occurred I was unable to run Quartus - the error message was "aborted, (core dumped)'.  Thing is - all of our other EDA tools including Modelsim still worked after the DNS change. Why was Quartus different? I dunno... I suspect some antiquated way (see Red Hat) of performing name lookups.  About 16 hours of debugging later using strace it was determined that Quartus was resorting to 'mdns' calls, and having a segmentation fault... but why?  It turns out - our DNS server was not allowing client machines that were non-windows boxes to perform BIND type operations. That is, when an IP address was checked out from the DHCP server - the name of the machine would not get updated in the DNS data base. Why this was crashing Quartus appears to be the way licenses are checked out - which is different from our other EDA tools.   Quartus attempts to identify the machine it's running on by performing some type of DNS lookup. And while I was able to 'ping' the machine I was running on, and get the correct machine name, the DNS server didn't know the machine's name - and therefore the Quartus licensing routine would pass an empty name to the license routine... causing it to crash.  During our panic, we tried running on a Red Hat box, and it worked. I wish this wasn't the case... because Red Hat is not going to be used on our production machines.  Anyway... if you suddenly experience "aborted (core dumped)" errors after a network infrastructure change at your business then look at DNS.   You can debug quartus using: strace -r quartus   and optionally strace -r -o log.txt quartus  Look for segmentation faults in the log file - as there are so many errors that are ignored - you'll never figure them all out - so focus on seg faults, or faults indicated at the time of the crash...  Jon