Short takes: SSH, custom ports, root and Synology NASs

This blog has been much maligned of late… I’d like to get more time to write and I have literally hundreds of part-written posts, some of which are now just a collection of links for me to unpick…

In the meantime, a couple of snippets that may be useless, or may help someone one day…

Using SSH with a custom port number

My Synology NAS complains about poor security if I leave SSH enabled on port 22. It’s fine if I change it to another port though (security by obscurity!). Connecting then needs a bit more work as it’s ssh user@ipaddress -p portnumber (found via the askubuntu forums)

Logging on to a Synology NAS from SSH as root

On a related topic, I recently needed to SSH to my NAS as root (not admin). ssh root@ipaddress -p portnumber¬†wasn’t authenticating correctly and then I found Synology’s advice on how to login to DSM with root permission via SSH/Telnet. It seems I have to first log on as admin, then sudo -i to elevate to root.

Synology Hyper Backup and DSM update failures

I have a Synology DS916+ NAS and, for the 9 months or so, I’ve been using it to back up my photos to Microsoft Azure. I’ve realised that they are being backed up in a format that’s unique to Synology’s Hyper Backup program, so I should probably see if there is an alternative that backs up the files in their native format but, more worryingly, this afternoon I noticed that backups had been failing for a few days. The logs weren’t much help (no detailed information) and a search on the ‘net didn’t turn much up either. For reference, this was the (very high level) information in the logs when viewed in the Hyper Backup GUI:

Information 2017/07/08 03:00:02 SYSTEM [Azure Blob] [Backup Photos to Microsoft Azure] Backup task started.
Error 2017/07/08 03:00:33 SYSTEM [Azure Blob] [Backup Photos to Microsoft Azure] Exception occured while backing up data.
Error 2017/07/08 03:00:36 SYSTEM [Azure Blob] [Backup Photos to Microsoft Azure] Failed to backup data.
Error 2017/07/08 03:00:36 SYSTEM [Azure Blob] [Backup Photos to Microsoft Azure] Failed to run backup task.

(Since then, I’ve found how to view detailed backup logs on a Synology NAS, thanks to a blog post by Jonathan Mumm, though in this case, the logs didn’t shine much of a light on the problem for me.)

I wondered if there were any DSM updates available that might fix things but, when I checked for updates, I got a message to say “Insufficient capacity for update. The system partition requires at least 400MB”. Googling suggested lots of manual file deletion and I was sure this was just a buildup of temp files (maybe to do with the failed backup), so I decided to reboot. After all, what do you do when a computer isn’t working as expected? Turn it off and on again!

After rebooting, attempts to update no longer produced an error (simply confirming that I’m up-to-date with DSM 6.1.2-15132) and the backup is now running nicely (it will take a few hours to complete as I added a few months’ worth of iPhone photos to the NAS earlier in the week, around about the time the backups started failing…)