sql database backups are failing with backup exec 2012

Hi,

I need help

Backup server - windows 2008 R2 enterprises.

Backup software - backup exec 2012

I have configured 8 sql database servers for backup, in ths 6 servers backup jobs are running fine and getting successful, except 2 sql server.

2 sql server´s backups are failing with below error.

 anyone help on this issue.

server 1-

Snapshot Technology: Initialization failure on: "sqldist.sistemas.dgtm.cl\MSSQLSERVER". Snapshot technology used: No.
The network connection failed during the snapshot. Check the network, and then run the job again.
V-79-57344-65305 - The database server is not responding. Backup set canceled.
V-79-57344-65305 - The database server is not responding. Backup set canceled.
 - Snapshot Technology: Initialization failure on: "\\sqldist.sistemas.dgtm.cl\C:". Snapshot technology used: No.
The network connection failed during the snapshot. Check the network, and then run the job again.
V-79-57344-65072 - The connection to target system has been lost. Backup set canceled.
V-79-57344-65072 - The connection to target system has been lost. Backup set canceled.
 

server 2-

 V-79-57344-65055 - Snapshot Technology: Initialization failure on: "sianalfa.sistemas.dgtm.cl". Snapshot technology used: No.
Snapshot technology error (0xE000FE1F): The device cannot be found.

Check the Windows Event Viewer for details.