Migrating from RHEL 7 to RHEL 8 servers

[hbouma]

We are in the process of testing out a migration of our DEV Nagios XI server from RHEL 7 to RHEL 8.

We have installed the Nagios XI instance on RHEL 8. Offloaded the database for the new install to our new RHEL 8 DB server. Changed the passwords as listed at https://assets.nagios.com/downloads/nag ... ios-XI.pdf.

During the restore process as listed at https://assets.nagios.com/downloads/nag ... ios-XI.pdf, we see that it is attempting to connect to the DB of the old XI server, not the IP of the new RHEL 8 DB server.

What would be the proper steps for migrating both the Nagios XI instance and the data in the MariaDB server from RHEL 7 to RHEL 8?

[gsmith]

Hi,

Please take a look at:
https://assets.nagios.com/downloads/nag ... Server.pdf

page 13 and on is what you need but you should probably review the whole document to be safe.

Please let us know how things go.

Thanks!

[hbouma]

Yes, we followed those steps, however, the files are being overwriten during the migration from the other server and pointing to the original RHEL 7 DB instead of our new RHEL 8 DB that we setup in the original configuration and offloading of the database.

For instance, the ndo.cfg file was changed from our setup pointing to the RHEL 8 DB to one that matched the Nagios XI source server's config file.

[gsmith]

Hi

So now follow that document starting on page 13 to make the changes so that the new RHEL8 XI server
uses the IP of the new RHEL 8 db server.

Thanks

[hbouma]

Just to make sure I understand this correctly:

Backup the source RHEL 7 Nagios XI server (Nagios-A) that uses MariaDB RHEL 7 server (Maria-A).
Restore the information to destination RHEL 8 Nagios XI server (Nagios-B).

Now, Nagios-B is connecting to the RHEL 7 MariaDB server Maria-A. We then follow the instructions for the offloading and dump the data from Maria-A to the RHEL 8 MariaDB server (Maria-B), update all the information in the Nagios-B server and start using the Nagios-B instance?

Is that correct? Would this actually move the historical RRD data and the check information about past checks?

[gsmith]

Hi

Yes that is correct.

Backup the source RHEL 7 Nagios XI server (Nagios-A) that uses MariaDB RHEL 7 server (Maria-A).
Restore the information to destination RHEL 8 Nagios XI server (Nagios-B).

Now, Nagios-B is connecting to the RHEL 7 MariaDB server Maria-A.

Correct.

We then follow the instructions for the offloading and dump the data from Maria-A to the RHEL 8 MariaDB server (Maria-B),

Yup - create the dbs on RHEL 8 MariaDB server (Maria-B), set up the firewall, test the db connectivity from (Nagios-B) to
RHEL 8 MariaDB server (Maria-B), rollover the db data from Maria-A to Maria-B; per pages 3 - 12 of https://assets.nagios.com/downloads/nag ... Server.pdf

update all the information in the Nagios-B server and start using the Nagios-B instance?

Yes, follow page 13 and onward of https://assets.nagios.com/downloads/nag ... Server.pdf

Would this actually move the historical RRD data and the check information about past checks?

Yes, the RRD data will come over with the Nagios-A to Nagios-B migration, and the past check
information is in the dbs that get moved from Maria-A to Maria-B

We encourage you to go through this process with Test servers. You should create an environment that reflects
your Prod environment as closely as possible. Then go through the upgrade. Our licensing agreement allows
you to do this.

Nagios XI License Policy
With every purchase we offer 3 separate activation of XI licenses. One for production, one for testing, and one for
high availability. We always recommend upgrading on a test server first before making changes to the production server.

Nagios License Entitlements
https://support.nagios.com/kb/article.php?id=145

Thanks

[hbouma]

Thank you. This is our DEV/TST server used for testing out these type of changes. We want to get it all figured out before we start moving on to our non DEV servers.

[gsmith]

No problem, I am glad you are doing a "dry run".

I am going to lock this thread, but if you run into anything during the migration
don't hesitate to create another post.

Thanks!