MySQL Bugs: #38409: Upgrading MySQL server needs an agent restart in order to show up on the UI

Bug #38409	Upgrading MySQL server needs an agent restart in order to show up on the UI
Submitted:	28 Jul 2008 18:14	Modified:	23 Jun 18:34
Reporter:	Diego Medina
Status:	Verified
Category:	Monitoring: Agent	Severity:	S3 (Non-critical)
Version:	2.0.0.7016	OS:	Any
Assigned to:	Kay Roepke	Target Version:
Tags:	windmill
Triage:	D3 (Medium)

Description:
If you are monitoring one instance of mysql server (mysqld) and then upgrade that
mysqld.

The new "version" of the mysql server will not show up on the UI

How to repeat:
1- install an order version of mysqld (5.0.x)
2- install the monitor
3- install the agent
4- start the agent, monitor and mysqld
5- see the mysqld instance show up on the dashboard
6- stop the mysqld
7- install a new version of the mysql server
8- start the new mysld
9- go to the UI, this server will not show up

The work around is to restart the agent, but for customers monitoring 30+ servers, we
would be adding one more step to each server upgrade.

The real solution is to collect the information the first time the agent connects to the
server.

Current MySQL implementations don't allow you to change the version dynamically so
further requests of the version number SHOULD NOT change, and are therefore pointless.

If the connection goes away (typical if you upgrade the server) the agent is
disconnected, so it connects again and collects the new version.

An entry was added to the 2.0 changelog:

Important Note: If you are monitoring one instance of MySQL server (mysqld) and then
upgrade that MySQL server, the correct version of the MySQL server is not displayed in
the Dashboard. This is a known issue that will be fixed in future versions of MySQL
Enterprise Monitor.

Diego Medina writes: 
For the case of a server upgrade, please see 
https://repoman.mysql.com/jira/browse/EM-3358

for a workaround.

Gary Whizin writes: 
* Workaround is to use the new Refresh feature on the menu on the Manage Servers page.
* Rename "Refresh" to "Refresh Inventory"
* Longterm should consider inventory deltas
* Meanwhile, Doc team should tell users to hit Refresh Inventory if they upgrade mysql