Hostname not set in OS causing solr not to function

[#1]

Version

Centos/RHEL 6.x (Cb Response 5.x)

Issue

Solr queries are returning with a 500 error and solr has an UnkownHostException error.

Symptoms

/var/log/cb/job-runner/job-runner.log:

2016-10-25 13:40:09 [11395] <err> [watchlist_search] HTTP 500 from solr: HTTPError('500 Server Error: Internal Server Error',); response: <Response [500]> 
2016-10-25 13:40:09 [11395] <err> [watchlist_search] Searcher query/tag exception in watchlist entry [Redacted] Redacted Hits (21) 
Traceback (most recent call last): 
File "/usr/lib/python2.6/site-packages/cb/maintenance/jobs/watchlist_searcher.py", line 95, in execute 
File "/usr/lib/python2.6/site-packages/cb/maintenance/jobs/watchlist_searcher.py", line 145, in _tag 
File "/opt/jenkins/builds/workspace/build-cbent-release-5.1.1-4/code/coreservices/src/cb/api/solr.py", line 842, in set_process_document 
File "/opt/jenkins/builds/workspace/build-cbent-release-5.1.1-4/code/coreservices/src/cb/utils/requests/models.py", line 714, in raise_for_status 
HTTPError: 500 Server Error: Internal Server Error 

/var/log/cb/solr/debug.log:

2016-10-25 13:40:09,875 - [ERROR] - from org.apache.solr.core.SolrCore in http-8080-13 
java.net.UnknownHostException: response: response: Name or service not known 

Cause

The hostname has not been set in the linux OS causing solr not to be able to return queries to other processes.

Solution

1. Verify that the environment doesn't know the hostname:
   

   [root@response ~]# hostname --fqdn
   hostname: Unknown host

2. Update your hostname to match the FQDN hostname in /etc/sysconfig/network
   

   HOSTNAME=myserver.domain.com

3. Also update the record held by hostname
   

   [root@response ~]# hostname myserver.domain.com

4. Commit changes
   

   /etc/init.d/network restart