SFTP Backup Fails on one VM only

#1

I am able to backup all my virtual machines except one. Every time the backup is attempted it backs up for a while and then this:

./vertical backup -t CORE --parallel AD-DNS2 --email
2017-11-11 16:49:53.830743 INFO PROGRAM_VERSION Vertical Backup 1.1.2
2017-11-11 16:49:54.724024 INFO LICENSE_INFO This license is only valid for home and non-production use
2017-11-11 16:49:54.724101 INFO LICENSE_INFO Licensed to Cluster-SM; expires on 2018-10-20
2017-11-11 16:49:55.520253 INFO STORAGE_CREATE Storage set to sftp://sftp_backup@10.0.1.16/volume1/SFTP/Vertical_Backup
2017-11-11 16:49:55.591781 INFO SNAPSHOT_GETALLVM Listing all virtual machines
2017-11-11 16:49:56.036929 INFO BACKUP_VM Backing up AD-DNS2, id: 6, vmx path: /vmfs/volumes/V-Storage/AD-DNS2_1/AD-DNS2.vmx, guest os: windows8Server64Guest
2017-11-11 16:49:56.154121 INFO BACKUP_NEW No previous backup found
2017-11-11 16:49:56.683831 INFO SNAPSHOT_POWER Virtual machine AD-DNS2 is powered on
2017-11-11 16:49:56.683951 INFO SNAPSHOT_REMOVE Removing all snapshots of AD-DNS2
2017-11-11 16:50:13.594343 INFO SNAPSHOT_CREATE Creating a new virtual machine snapshot for AD-DNS2
2017-11-11 16:51:41.854242 INFO BACKUP_UPLOAD Uploaded file /vmfs/volumes/V-Storage/AD-DNS2_1/AD-DNS2.vmdk
2017-11-11 16:51:41.867915 INFO BACKUP_UPLOAD Uploading file AD-DNS2-flat.vmdk
2017-11-11 17:03:31.105152 INFO BACKUP_UPLOAD Uploaded file AD-DNS2-flat.vmdk 57.75MB/s 00:11:49
2017-11-11 17:03:31.172490 INFO BACKUP_UPLOAD Uploaded file AD-DNS2.vmx
2017-11-11 17:03:36.732154 WARNING SFTP_RETRY SSH exception: Server connection dropped: ; reconnecting after 3.0 seconds
2017-11-11 17:03:40.539512 WARNING SFTP_RETRY SSH exception: Server connection dropped: ; reconnecting after 4.4 seconds
2017-11-11 17:03:46.625163 WARNING SFTP_RETRY SSH exception: Server connection dropped: ; reconnecting after 21.9 seconds
2017-11-11 17:04:09.195372 WARNING SFTP_RETRY SSH exception: Server connection dropped: ; reconnecting after 133.7 seconds
2017-11-11 17:06:23.719133 WARNING SFTP_RETRY SSH exception: Server connection dropped: ; reconnecting after 317.0 seconds
2017-11-11 17:11:40.738395 ERROR SFTP_RETRY Maximum number of retries attempted in uploadFile
2017-11-11 17:11:40.738710 INFO SNAPSHOT_REMOVE Removing all snapshots of AD-DNS2

This ONLY happens on this VM. I’m lost. All backups have the same host and same destination shared storage.

#2

I bet the sftp server is a Synology NAS. They appear to have difficulty taking paths that are longer than a certain value and forcefully close connections. It happens to this VM because it probably has longer name than other VMs.

#3

It is a synology. The VM name is AD-DNS2. I am able to successfully backup vcsa-psc though. Is there a workaround to get this to function?

#4

Mount the Synology NAS as an NFS drive should work (and maybe faster than SFTP).

#5

That worked! Mounting the datastore to the ESXi hosts did it and it is a faster transfer. Thanks!