Backup fails: 'Can't start new thread'


#1

Been running automated backups and every time it tries it fails with the same vm and the same error:

2018-02-05 08:21:46.021354 INFO SNAPSHOT_POWER Virtual machine media is powered on
2018-02-05 08:21:46.021985 INFO SNAPSHOT_REMOVE Removing all snapshots of media
2018-02-05 08:21:47.268161 INFO BACKUP_EXCLUDE Disk file '/vmfs/volumes/5a6e532f-f81bfcdd-2324-94de807b3d65/nfs/nfs_1.vmdk' is excluded from backup
2018-02-05 08:21:47.268648 INFO SNAPSHOT_CREATE Creating a new virtual machine snapshot for media
2018-02-05 08:21:51.751230 INFO BACKUP_EXCLUDE Disk file '/vmfs/volumes/5a6e532f-f81bfcdd-2324-94de807b3d65/nfs/nfs_1.vmdk' is excluded from backup
2018-02-05 08:21:52.712510 INFO BACKUP_UPLOAD Uploaded file /vmfs/volumes/datastore1/media/media.vmdk
2018-02-05 08:21:52.714954 INFO BACKUP_UPLOAD Uploading file media-flat.vmdk
2018-02-05 08:21:52.716315 INFO RESTORE_THREAD Using 32 uploading threads
2018-02-05 08:21:52.727566 INFO SNAPSHOT_REMOVE Removing all snapshots of media
2018-02-05 08:21:52.788541 ERROR COMMAND_IO Failed to read input from command '/bin/vim-cmd vmsvc/snapshot.removeall 6': can't start new thread

Prior to this error, it successfully backs up a few other vms. This is the only vm with a disk exclusion, all other options are the same between all vms.

Help appreciated.


#2

When it says it can’t start new thread it is probably out of memory – processes running on ESXi hosts only have a very limited amount of memory. It would definitely help if you can reduce the number threads.