Error 1400, when performing remote backup using 2 devices

Summary: remote backup works for a small folder, and fails on large folder

I have just purchased 2 new “WD cloud mirror” each 6TB
upgraded both of them to firmware 2.10.302
I enabled SSH on both of them
I enabled “remote server” on both of them
I enabled remote backups on both of them

I configured 2 remote backup jobs
one works fine (folder 73MB in size)
the other job fails, with error 1400 (folder 2.5TB in size)

it worked once, first time I configured, and failed ever since, nothing can make it succeed.

when I try remote backup for second job, it displays error:

Remote Backup Error
An error occurred for the remote backup job named wk_sync_master. Please check the backup job detail.
Tuesday, 24 November, 2015 7:34:21 PM

I am trying all the above on LAN (not wan, not over internet)
the primary “my cloud mirror” IP is
and the backup IP is
both are static (no DHCP)

I can ping both drives from my laptop
I can connect to both using ssh from my laptop (user sshd & password)

check screenshots for more details.

Appreciate feedback and help in this regard

As a recommendation, contact WD Support for direct assistance on this case to see why is not working on the larger backup.

WD Contact info:

Thanks for your feedback, I am opening a case right now

2 posts were split to a new topic: Error 1400 on a My Cloud Mirror