We mirroring a couple of Snaplock Enterprise Volumes beside some normal Voluems to a second system and doing a dump to tape from there. While the dump for the normal Volumes runs fine, the dumps for the Snaplocked volumes are interrrupted during Phase I.
To eleminate any problems with the Backup Software I did a dump to NULL on console:
"dump 0uvfb null 256 /vol/vol"
In the log I see that after 5 min the Phase I is interrupted and the dump is stopped.