When upgrading FortiSIEM to v7.5.1, the error 'Upgrade Rocky Linux 8 to Rocky Linux 9' may emerge and prevent the upgrade to continue with the next details (from sh upgrade.sh command output or /usr/local/upgrade/logs/ansible.log):
UPGRADE | Upgrade Rocky Linux 8 to Rocky Linux 9 ...| localhost | FAILED | 10m19s
...
Error downloading packages:
...Cannot download, all mirrors were already tried without success
This may happen in Azure environments.
To prevent the error or fix it after a snapshot restoration, run these commands in the console after following the upgrade steps:
cd /opt/upgrade
7za x FSM_Upgrade_All_7.5.1_build0620.zip
Replace the '/opt/upgrade/FSM_Upgrade_All_7.5.1_build0620/install/files/upgrade_rocky8_to_rocky9.sh' with the file attached at the bottom of this article, and run the following from the node CLI as the root user:
rm -rf /opt/upgrade/FSM_Upgrade_All_7.5.1_build0620/install/files/upgrade_rocky8_to_rocky9.sh
cd /
tar -xzvf /tmp/upgrade_rocky8_to_rocky9.sh.tar.gz
chmod 755 /opt/upgrade/FSM_Upgrade_All_7.5.1_build0620/install/files/upgrade_rocky8_to_rocky9.sh
Finally, run the upgrade.
Attachment: upgrade_rocky8_to_rocky9.sh.tar.gz. | 
