SuperTekBoy

V-79-57344-65072 – The connection to target system has been lost. Backup set canceled.

I ran into this error recently at one of my clients with their new Backup Exec 2012 implementation. The jobs would sometimes work, but mostly they would fail with the error above. They would also fail at seemingly random byte counts. The implementation was backing up two servers. One of the servers was also the media server and this local backup always succeeded as expected and without incident. The other server, the one that was often failing, was the one with the remote agent.

This made me quickly look towards the network. As a test, I kicked off the problematic backup and monitored the network bandwidth usage in Task Manager on both servers. I also had a continuous ping going between the two servers. The first thing that became apparent was that the network bandwidth (100Mb switch) was completely saturated during the backup. Both servers continually reported a steady hold at 100% network utilization.

Then it happened. At first, I saw the continuous ping start to fail between the two servers. Then I noticed the network links as being reported down on both servers. I could only assume at this point the switch that connected these two servers together was having problems. I logged into the switch and checked the uptime. Lo and behold the switches uptime was just a couple of minutes. I repeated this test a few more times and even tried different switch ports and network cables. Same result every time. The switch kept rebooting. I could only assume this older switch could not handle the constant 100% network load.

UPDATED: This same option also exists in Backup Exec 2014. These instructions are also the same for 2014. However, in 2014 there is also a checkbox where you can disable this feature. Click here for a screenshot.

I ran across this issue recently when troubleshooting why four removable backup drives in a drive pool kept going into read-only mode at seemingly random intervals. Initially, I would go into the drive properties, switch the drive to allow write operations, only for it go back to read-only just a few weeks later.

My client was using 4 removable USB drives in rotation. These drives were all in one drive pool in Backup Exec. They would swap the drives out weekly, so each drive would be offline for as much as 3 weeks.

What I found, which appears to be new to Backup Exec 2012, is a setting that automatically switches any removable disk to read-only mode after a set number of days. The default is 14 days. I’ve since increased this number past 3 weeks and had no problems.