Monitoring und debugging
Install telnet
telnet localhost 3111
Then you can type one of the „Zookeeper 4 letter commands“ e.g.: stat
https://zookeeper.apache.org/doc/r3.4.8/zookeeperAdmin.html#sc_zkCommands
If the telnet command is not available, it can be used in the Windows console (with administrator rights) as follows
can be installed:
pkgmgr /iu:'TelnetClient'
Nc
Nc stands for Netcat and is a simple but powerful tool from the Unix world for sending network requests. The tool nc for Windows can be downloaded here:
https://joncraton.org/blog/46/netcat-for-windows/
2. Monitoring commands for zookeepers
Automated Monitoring
Example :
echo ruok | nc 127.0.0.1 5111
„Imok“ should appear as a response..
More examples: https://blog.serverdensity.com/how-to-monitor-zookeeper/
3. Monitoring commands for Solr
The status of a Solr instance can be queried via FTS-Index/bin/solr.cmd:
Status of a SolrCloud instance (to be recognized by the JSON node "cloud" with the connection string ZK_HOST)
In addition, the status information can also be queried as JSON: http://localhost:8983/solr/WebOffice/admin/system
The Solr Admin UI is available as follows: http://localhost:8983/solr/
4. Debugging
If the services are not available as desired, it is necessary to check the individual components to find out what is already running successfully and where the problems must be dealt with.
It is advisable to temporarily stop the service 'WebOffice FTS Index and start Solr manually instead. This is possible via the WebOffice script FTS-Index/bin/solr.cmd.
solr start -p {portnummer}
solr stop -all
solr status
Detailed help texts are also available for all available commands:
solr -h
Solr start -h
Escaping special characters
If errors occur when starting Solr, this can be due to invalid characters in configured values, e.g. because a special character such as a parenthesis or similar must be escaped.
For the paths to the keystores (SOLR_SSL_KEY_STORE und SOLR_SSL_TRUST_STORE) in the configuration file solr.in.cmd a bracket (both the opening and closing) must be masked with five^ (circumflex).
Configuration file solr.in.cmd