Pmm2 Client/Pmm3

Percona Monitoring and Management (PMM) PMM 3.x
1

I know what my issue is, but I could swear I had it working on some systems somewhere. I just can’t figure out where or how I did it.

My PMM Server is version 3.0.0. I have some old CentOS 7.9 systems still in use (we’re having issues updating some software to RHEL 8/9 due to library compatibility, which we’re working through).

I could swear that I had pmm2-client-2.42.0-6.el7 reporting metrics back to the PMM Server 3.0.0. I think a yum remove and reconfiguration of the agent was done, and now I can’t, for the life of me, find any combination that works to get it to report back to the PMM 3.0.0 server.

Am I screwed after re configuring the agent, or is there any potential workaround — other than setting up another PMM2 server for it to dial home to? I also tried the lowest version of the pmm3 client

2

Hey @meyerder,
Are you trying to reach a PMM3 server with a PMM2 client? Else, are you having issues with installing the pmm client 2 in Cent OS 7.9? Please clarify.

If you are trying to scrape metrics through pmm2 client to the pmm3 server, you can do with <PMM 3.3 server. But it is not guaranteed that everything will work as expected. It is mandatory to use a similar version of pmm client as your pmm server’s version.

From doc:

PMM 3 Server provides limited support for PMM 2 Clients (metrics and Query Analytics only). This support will be removed in PMM 3.3.

We will need more details about your problem clearly to help you further.

Regards,
Vinodh Guruji

3

@Vinodh_Krishnaswamy Yes.. It was noted as such

Path
All PMM clients were removed from the Centos 7.9 system
PMM server = 3.0.0 II understand after 3.3 server any PMM2 Clients will not work)

I have tried to install
pmm-client (1.x Yea I saw that and said nope)
percona release disable all
enabled the pmm2-client repo
installed the pmm2 client 2.42
pmm-admin --version
ProjectName: pmm-admin

Version: 2.42.0 Failed to register pmm-agent on PMM Server: Endpoint not found: /v1/management/Node/Register, http method: POST.

PMM Server Current version: 3.0.0 (January 23, 2025 UTC)

U cant seem to get a version for pmm3 to install on 7.9 but according to the docs what I am doing SHOULD work

The Mgmt server when going to it does this..

{
“code”: 5,
“message”: “Endpoint not found: /v1/management/Node/Register, http method: GET”,
“details”:
}

4

Hello @meyerder, we supported only compatibility for metrics, it was done for existing PMM clients. Register and inventory operations wasn’t planned to keep working. This was done for users who update server first and then upgrade clients.

1 Like
5

Crap.. I had my regular process (even with doing logging) to remove the pmm agent and make sure that I had a soft link from the /usr folder to an application folder (some of the data sometimes caused the /usr folder to fill up and cause issues)

6

As a workaround you can do following:

  1. Install PMM 3 Client
  2. configure everything on some empty machine,
  3. add services using --skip-connection-check flag
  4. copy pmm-agent.yml file from /usr/local/percona/pmm/config/pmm-agent.yml on new machine to /usr/local/percona/pmm2/config/pmm-agent.yml on old machine.
  5. Stop PMM 3 Client on new machine and start PMM 2 Client

It wasn’t tested, but might work.