On 10/15/2018 1:30 PM, Dasarathi Minjur wrote:
We have a Hadoop cluster with Solr 6.3 running as service. After an OS security patching, when the cluster was restarted, Solr Cloud is up but the shards are down all the time. No specific messages in Solr.log or console logs. Tried restarting solr but that didn't help. Any pointers to get the shards up will be helpful. Thanks for taking time to respond.
Not having anything show up in the log is worrying. Normally if things don't come up, at least one of the nodes in the cloud should log SOMETHING to indicate what went wrong. But given the age of the version you're running, I'm not really surprised by ANY strange behavior.
6.3.0 was released two years ago - which is a LONG time in open source. Solr has a more aggressive release pace than a lot of other software packages. There are eleven 6.x releases after 6.3.0, and twenty total releases after 6.3.0 if you count 7.x as well. The 6.x line in particular had a very large number of SolrCloud-related bugfixes and improvements, with major focus on stability.
Version 6.3 won't see any fixes. Even 6.6.x, which is the only branch in 6.x that will EVER see any fixes, is only going to get really major updates, particularly security bugs.
All that goes to say ... you might have to upgrade Solr to even troubleshoot the problem, if 6.3.0 logs nothing. If a problem is found, you'll definitely have to upgrade to get a fix, unless you're willing to patch and build the 6.3.0 version yourself.
Thanks, Shawn
