The best practices for installing Red Hat Enterprise Linux or Rocky Linux and the associated repositories on your system are listed below. Systems installed or configured differently might require additional steps.

You must install Red Hat Enterprise Linux or Rocky Linux according to Red Hat best practices. Due to end-of-life support for CentOS 8.x versions, compatible versions of CentOS 8.x are not recommended.
While installing the ONTAP Mediator service on Red Hat Enterprise Linux or Rocky Linux, the system must have access to the appropriate repository so that the installation program can access and install all the required software dependencies.
For the yum installer to find dependent software in the Red Hat Enterprise Linux repositories, you must have registered the system during the Red Hat Enterprise Linux installation or afterwards by using a valid Red Hat subscription.

See the Red Hat documentation for information about the Red Hat Subscription Manager.
The following ports must be unused and available for the Mediator:
- 31784
- 3260
If using a third-party firewall: refer to Firewall requirements for ONTAP Mediator
If the Linux host is in a location without access to the internet, you must ensure that the required packages are available in a local repository.

If you are using Link Aggregation Control Protocol (LACP) in a Linux environment, you must correctly configure the kernel and make sure the sysctl net.ipv4.conf.all.arp_ignore is set to "2".

What you’ll need

The following packages are required by the ONTAP Mediator service:

All RHEL/CentOS versions	Additional packages for RHEL 8.x / Rocky Linux 8	Additional packages for RHEL 9.x / Rocky Linux 9
openssl openssl-devel kernel-devel-$ (uname -r) gcc make libselinux-utils patch bzip2 perl-Data-Dumper perl-ExtUtils-MakeMaker efibootmgr mokutil	python3-pip elfutils-libelf-devel policycoreutils-python-utils redhat-lsb-core python39 python39-devel	python3-pip elfutils-libelf-devel policycoreutils-python-utils python3 python3-devel

All RHEL/CentOS versions

Additional packages for RHEL 8.x / Rocky Linux 8

Additional packages for RHEL 9.x / Rocky Linux 9

openssl
openssl-devel
kernel-devel-$ (uname -r)
gcc
make
libselinux-utils
patch
bzip2
perl-Data-Dumper
perl-ExtUtils-MakeMaker
efibootmgr
mokutil

python3-pip
elfutils-libelf-devel
policycoreutils-python-utils
redhat-lsb-core
python39
python39-devel

python3-pip
elfutils-libelf-devel
policycoreutils-python-utils
python3
python3-devel

The Mediator installation package is a self-extracting compressed tar file that includes:

An RPM file containing all dependencies that cannot be obtained from the supported release’s repository.
An install script.

A valid SSL certification is recommended.

About this task

When you upgrade the host OS for ONTAP Mediator to a later major version (for example, from 7.x to 8.x) using the leapp-upgrade tool, you must uninstall ONTAP Mediator because the tool tries to detect new versions of any RPMs that are installed in the repositories that are registered with the system.

Because an .rpm file was installed as part of the ONTAP Mediator installer, it is included in that search. However, because that .rpm file was unpacked as part of the installer and not downloaded from a registered repository, an upgrade cannot be found. In this case, the leapp-upgrade tool uninstalls the package.

In order to preserve the log files, which will be used to triage support cases, you should back up the files prior to doing an OS upgrade and restore them after a reinstall of the ONTAP Mediator package. Because the ONTAP Mediator is being reinstalled, any ONTAP Clusters that are connected to it will need to be reconnected after the new installation.

The following steps should be performed in order. Immediately after you reinstall ONTAP Mediator, you should stop the ontap_mediator service, replace the log files, and restart the service. This will ensure logs will not be lost.

Steps

Back up the log files.

[rootmediator-host ~]# tar -czf ontap_mediator_file_backup.tgz -C /opt/netapp/lib/ontap_mediator ./log ./ontap_mediator/server_config/ontap_mediator.user_config.yaml
[rootmediator-host ~]# tar -tf ontap_mediator_file_backup.tgz
./log/
./log/ontap_mediator.log
./log/scstadmin.log
./log/ontap_mediator_stdout.log
./log/ontap_mediator_requests.log
./log/install_20230419134611.log
./log/scst.log
./log/ontap_mediator_syslog.log
./ontap_mediator/server_config/ontap_mediator.user_config.yaml
[rootmediator-host ~]#

Perform upgrade with leapp-upgrade tool.

[rootmediator-host ~]# leapp preupgrade --target 8.4
  ..<snip upgrade checks>..
  ..<fix issues found>..
[rootmediator-host ~]# leapp upgrade --target 8.4
  ..<snip upgrade>..
[rootmediator-host ~]# cat /etc/os-release | head -2
NAME="Red Hat Enterprise Linux"
VERSION="8.4 (Ootpa)"
[rootmediator-host ~]#

Reinstall ONTAP Mediator.

Perform the rest of the steps immediately after reinstalling ONTAP Mediator to prevent a loss of log files.

[rootmediator-host ~]# ontap-mediator-1.6.0/ontap-mediator-1.6.0

ONTAP Mediator: Self Extracting Installer

  ..<snip installation>..
[rootmediator-host ~]#

Stop the ontap_mediator service.

[rootmediator-host ~]# systemctl stop ontap_mediator
[rootmediator-host ~]#

Replace the log files.

[rootmediator-host ~]# tar -xf ontap_mediator_log_backup.tgz -C /opt/netapp/lib/ontap_mediator
[rootmediator-host ~]#

Start the ontap_mediator service.

[rootmediator-host ~]# systemctl start ontap_mediator
[rootmediator-host ~]#

Reconnect all ONTAP clusters to the upgraded ONTAP Mediator

Procedure for MetroCluster over IP

siteA::> metrocluster configuration-settings mediator show
Mediator IP     Port    Node                    Configuration Connection
                                                Status        Status
--------------- ------- ----------------------- ------------- -----------
172.31.40.122
                31784   siteA-node2             true          false
                        siteA-node1             true          false
                        siteB-node2             true          false
                        siteB-node2             true          false
siteA::> metrocluster configuration-settings mediator remove
Removing the mediator and disabling Automatic Unplanned Switchover. It may take a few minutes to complete.
Please enter the username for the mediator: mediatoradmin
Please enter the password for the mediator:
Confirm the mediator password:
Automatic Unplanned Switchover is disabled for all nodes...
Removing mediator mailboxes...
Successfully removed the mediator.

siteA::> metrocluster configuration-settings mediator add -mediator-address 172.31.40.122
Adding the mediator and enabling Automatic Unplanned Switchover. It may take a few minutes to complete.
Please enter the username for the mediator: mediatoradmin
Please enter the password for the mediator:
Confirm the mediator password:
Successfully added the mediator.

siteA::> metrocluster configuration-settings mediator show
Mediator IP     Port    Node                    Configuration Connection
                                                Status        Status
--------------- ------- ----------------------- ------------- -----------
172.31.40.122
                31784   siteA-node2             true          true
                        siteA-node1             true          true
                        siteB-node2             true          true
                        siteB-node2             true          true
siteA::>

Procedure for SnapMirror active sync

For SnapMirror active sync, if you installed your TLS certificate outside of the /opt/netapp directory, then you will not need to reinstall it. If you were using the default generated self-signed certificate or put your custom certificate in the /opt/netapp directory, then you should back it up and restore it.

peer1::> snapmirror mediator show
Mediator Address Peer Cluster     Connection Status Quorum Status
---------------- ---------------- ----------------- -------------
172.31.49.237    peer2            unreachable       true

peer1::> snapmirror mediator remove -mediator-address 172.31.49.237 -peer-cluster peer2

Info: [Job 39] 'mediator remove' job queued

peer1::> job show -id 39
                            Owning
Job ID Name                 Vserver    Node           State
------ -------------------- ---------- -------------- ----------
39     mediator remove      peer1      peer1-node1    Success
     Description: Removing entry in mediator

peer1::> security certificate show -common-name ONTAPMediatorCA
Vserver    Serial Number   Certificate Name                       Type
---------- --------------- -------------------------------------- ------------
peer1
        4A790360081F41145E14C5D7CE721DC6C210007F
                        ONTAPMediatorCA                        server-ca
    Certificate Authority: ONTAP Mediator CA
        Expiration Date: Mon Apr 17 10:27:54 2073

peer1::> security certificate delete -common-name ONTAPMediatorCA *
1 entry was deleted.

 peer1::> security certificate install -type server-ca -vserver peer1

Please enter Certificate: Press <Enter> when done
  ..<snip ONTAP Mediator CA public key>..

You should keep a copy of the CA-signed digital certificate for future reference.

The installed certificate's CA and serial number for reference:
CA: ONTAP Mediator CA
serial: 44786524464C5113D5EC966779D3002135EA4254

The certificate's generated name for reference: ONTAPMediatorCA

peer2::> security certificate delete -common-name ONTAPMediatorCA *
1 entry was deleted.

peer2::> security certificate install -type server-ca -vserver peer2

 Please enter Certificate: Press <Enter> when done
..<snip ONTAP Mediator CA public key>..


You should keep a copy of the CA-signed digital certificate for future reference.

The installed certificate's CA and serial number for reference:
CA: ONTAP Mediator CA
serial: 44786524464C5113D5EC966779D3002135EA4254

The certificate's generated name for reference: ONTAPMediatorCA

peer1::> snapmirror mediator add -mediator-address 172.31.49.237 -peer-cluster peer2 -username mediatoradmin

Notice: Enter the mediator password.

Enter the password:
Enter the password again:

Info: [Job: 43] 'mediator add' job queued

peer1::> job show -id 43
                            Owning
Job ID Name                 Vserver    Node           State
------ -------------------- ---------- -------------- ----------
43     mediator add         peer1      peer1-node2    Success
    Description: Creating a mediator entry

peer1::> snapmirror mediator show
Mediator Address Peer Cluster     Connection Status Quorum Status
---------------- ---------------- ----------------- -------------
172.31.49.237    peer2            connected         true

peer1::>