Basic troubleshooting when encountering issues saving the configuration.
Check if the Nachos service is running
Log in to the Monitor server with SSH, and check if the nachos service is running.
If the service is inactive, try to start it again.
If the service fails to start, refer to the status output or logs for clues.
Check the web console when trying to save
When on the save page, open the browsers console (ctrl + shift + c in Chrome), and select the save button. Next switch to the console tab, and click on save. The console log might show clues as to why the save fails. For example this console log indicates that the nachos service might be down.
The logs are located in /var/log/op5/nachos.log
The configuration is located in /opt/monitor/nachos/nachos.cfg.
Stuck in "Export already in progress"
This is a Nacoma related issue, and might occur in the new service as well. When an export stats, an object lock entry is inserted into the objlocks table in the Nacoma database. This entry is valid for five minutes, and is removed when the export has finished. In certain circumstances the entry might not be removed, for example when reaching PHP's max_exection_time limit in old Nacoma, which should not be an issue in the new service as it does not use PHP. If a user encounters this problem and want to unlock the database without waiting for the entry to expire, it is possible to truncate the objlocks table:
Access denied for user 'x'@'x'
If there is a line in the log file looking like this:
There can be multiple reasons why this problem is encountered. Most common reason is having "skip-networking" option set in /etc/my.cnf. The workaround is to use the MySQL Unix socket instead of TCP/IP.
Open /opt/monitor/nachos/nachos.cfg, and under [database] and [nacoma] add '?unix_socket=/var/lib/mysql/mysql.sock' to the connection variable, and remove ':3306'.
Another reason could be wrong user credentials. Make sure they are correct.
Save the file and restart the nachos service:
Missing exports table
This can happen when having "skip-networking" in /etc/my.cnf during the installation of Nachos. This oneliner will recreate the table.
Reverting to old functionality
Last resort in case of emergency.