perfSONAR User Q&A and Other Discussion

[Trond Endrestøl <>]

On Fri, 6 Oct 2017 10:49-0400, Andrew Lake wrote:

> I think there is indeed an issue with cassandra’s default config and
> IPv6-only hosts. Can you try the following:
> 
> 1. Open  /etc/cassandra/conf/cassandra-env.sh
> 2. Find and comment-out the line JVM_OPTS=“$JVM_OPTS -Djava.net
> .preferIPv4Stack=true”
> 3. Save the changes.
> 4. Restart cassandra with systemctl restart cassandra
> 
> Might want to double check there are no other references to
> -Djava.net.preferIPv4Stack=true
> in that file, mine just had the one. Also since you have been changing
> /etc/hosts, make sure localhost still resolves to ::1. Its possible we may
> need to play with the Java opts some more, but hopefully that is all you
> need. Seems to be a known issue with cassandra. We aren’t the authors of
> the cassandra RPM, but if that indeed fixes your issue we can look at
> having one of our packages correct that issue on install (it won’t be the
> first time we have had to some hand-holding for cassandra’s RPM).
> 
> Also, as an aside, there should be no requirement to disable your firewall.
> I think you said that didn’t work anyways but all communication with
> cassandra is done on localhost and should not be affected by the host
> firewall.

I reverted all my IPv4 perversion, commented out the IPv4Stack line in 
/etc/cassandra/conf/cassandra-env.sh, and rebooted the whole system.

Cassandra might be running IPv6 only now, but the web interface shows 
Error loading test listing: Internal Server Error. Previously it 
showed something else, but no results from any test.

-- 
Trond.