# Pmm2 Client/Pmm3 **URL:** \ **Category:** PMM 3.x\ **Created:** [June 25, 2025, 3:15am UTC](https://forums.percona.com/t/pmm2-client-pmm3/38432 "2025-06-25T03:15:16Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![meyerder](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/meyerder/32/16994_2.png) [@meyerder](https://forums.percona.com/u/meyerder)\ **Post date:** [June 25, 2025, 3:15am UTC](https://forums.percona.com/t/pmm2-client-pmm3/38432/1 "2025-06-25T03:15:16Z")
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 ---
**Author:** ![Vinodh\_Krishnaswamy](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/vinodh_krishnaswamy/32/46_2.png) [@Vinodh\_Krishnaswamy](https://forums.percona.com/u/Vinodh_Krishnaswamy)\ **Post date:** [June 25, 2025, 7:34am UTC](https://forums.percona.com/t/pmm2-client-pmm3/38432/2 "2025-06-25T07:34:51Z")
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 \ **[Percona Monitoring and Management - Migrate PMM 2 to PMM 3](https://docs.percona.com/percona-monitoring-and-management/3/pmm-upgrade/migrating_from_pmm_2.html#step-3-migrate-pmm-2-clients-to-pmm-3)** > > PMM 3 introduces significant architectural changes that require a gradual transition from PMM 2. > 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 ---
**Author:** ![meyerder](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/meyerder/32/16994_2.png) [@meyerder](https://forums.percona.com/u/meyerder)\ **Post date:** [June 25, 2025, 3:56pm UTC](https://forums.percona.com/t/pmm2-client-pmm3/38432/3 "2025-06-25T15:56:02Z")
@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”: } ---
**Author:** ![nurlan](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/nurlan/32/1523_2.png) [@nurlan](https://forums.percona.com/u/nurlan)\ **Post date:** [June 26, 2025, 10:45am UTC](https://forums.percona.com/t/pmm2-client-pmm3/38432/4 "2025-06-26T10:45:41Z")
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. ---
**Author:** ![meyerder](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/meyerder/32/16994_2.png) [@meyerder](https://forums.percona.com/u/meyerder)\ **Post date:** [June 26, 2025, 3:53pm UTC](https://forums.percona.com/t/pmm2-client-pmm3/38432/5 "2025-06-26T15:53:27Z")
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) ---
**Author:** ![nurlan](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/nurlan/32/1523_2.png) [@nurlan](https://forums.percona.com/u/nurlan)\ **Post date:** [June 27, 2025, 11:41am UTC](https://forums.percona.com/t/pmm2-client-pmm3/38432/6 "2025-06-27T11:41:08Z")
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.