Backup of a w2102-host with 2 hyper-guest (also on 2012) present a success or a failure. since this happens we don't change something on the 3 machines and 1 day it works, one day it fails. Latest error V-79-57344-34108, the day before on guest-a, yesterday on guest-b. Other error-codes are: V-79-40960-38467, V-79-57344-33967, V-57344-65033, V-79-57344-38726. Both guests are production-server and in daily use. After a reboot of the host, the backup may work or not.
BE2012 , SP3, HF213186
OS on all 3 machines are actually patched
What i found was fingerprintdiskmap.txt in c:\program files\symantec\BackuExec\RAWS\DATA\Hyper-V\Temp\5724f93a-..-..-...-..\9999....-..-..-..-\ with the following content:
fallbacktofull=false
M:\Hyper-V_Machines\xxxx\xxxx_c.vhd fingerprint0000.db
M:\Hyper-V_Machines\xxxx\xxxx_d.vhd fingerprint0001.db
fingerprint0000.db is 41024kb
fingerprint0001.db is missing
The guest with the error, does not appear on the hyper-v-manager, if you connect remotely to the host. on the hyper-v-manager on the host, the failing guest is still backing-up in his state, but the guest is online and the app is working fine and can be remotely connected.