Hi
Backup exec 12.5 can only be installed on Windows platform as MEDIA SERVER
Hence answer to question 1 :
Q : "Can we define the Unix server as the Media server??"
A : No .
But you can define unix only as 'unix as media server AGENT' ( it just keeps major info of catalogs -IT IS NOT MEDIA SERVER)
Qeustion 2 :
Yes you can protect your whole ESX server (provided agent is installed for same)
Refer the software compatiblity link BE 12.5 : Page 33 of 69
ftp://exftpp.symantec.com/pub/support/products/Backup_Exec_for_WindowsNT/307063.pdf
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