If you have HP os vSphere VSA, you may run into a problem if your entire environment goes down due to an power outage, for example. After booting back, the ESX servers will not find the VSA resident LUNs (obviously) because the VM was not powered on when the ESX rescanned the LUNs and datastores, requiring an manual rescan after everything is booted.
A simple way to fix this automatically is to script a manual rescan after 5 minutes of the boot of all ESX servers (or more time if needed):
1. Login to the ESX servers using SSH. Please place the host in maintenance mode before chenging anything for safety.
2. Edit the /etc/rc.local file
3. Add the following lines at the end of the file:
sleep 300
esxcfg-rescan -A
4. Run the “/sbin/auto-backup.sh” command.
You can test it by bringing the entire environment down and up again 
See you!
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