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…)

Using rsync to keep folders in sync on a Synology Diskstation NAS

Now I have backups working between my Synology Diskstation NAS and a storage account in Microsoft Azure (with over half a TB of photos so far backed up in the cloud), the next stage is to consolidate some more images into the folder that the backup works from.

I don’t want to remove them from their source (which in this case is the copy of my OneDrive data on my home drive) but I do want to archive all of the iPhone images I have there to the master photos folder so they are included in the backup.

Reading around the Synology forums suggests that this is not as straightforward as one might think. It appears there’s no easy way to synchronise two folders on the same NAS within the DSM software; but then I stumbled across Zarino Zappia (@zarino)’s post about a Synology-flavoured rsync backup script.

By following Zarino’s advice and using ssh to connect to the box as admin, I was able to achieve what I wanted with the following command:

rsync --itemize-changes --archive --progress --verbose --inplace --exclude '*@SynoResource' --exclude '@eaDir' --exclude '*.vsmeta' --exclude '.DS_Store' --exclude 'Thumbs.db' /volume1/homes/mark/OneDrive/iPhone\ Photos/ /volume1/photos/Digital\ Photos\ \(Master\)/Mark\'s\ iPhone/

(BTW, right click is the way to paste text to the command line in PuTTY!)

Some people on the Synology forums had suggested synchronising via another computer on the network would be fast! That sounds strange to me – logically a copy will always be faster on a single device with no network in between. For reference, it took about 20 minutes to rsync 32GB of images/videos on my on my DS916+.

Incidentally, the Error 23 in the screen shots was actually a typo in my command (missing space before one of the –exclude options). I re-ran with –dry-run to see which files were not transferred…

The next step will be to script this and get it running as a scheduled task but that can wait for another day…

My first few weeks with a Synology Diskstation NAS

Earlier this summer, I bought myself a new NAS. I’d lost faith in my old Netgear ReadyNAS devices a while ago, after a failure took out both halves of a RAID 1 mirror and I lost all the data on one of them. That actually taught me two important lessons:

  1. Data doesn’t exist unless it’s backed up in at least two places.
  2. RAID 1 is not suitable for fault-tolerant backups.

As I wrote a few weeks ago, my new model is to get all of the data into one place, then sync/archive as appropriate to the cloud. Anything on any other PCs, external disks, etc. should be considered transient.

For the device itself, it seems that there are only really two vendors to consider – QNAP or Synology (maybe a Drobo). I chose Synology – and elected to go with a 4-bay model, picking up a Synology Diskstation DS916+ (8GB) and kitting it out with 4 Hitachi (HGST) Deskstar NAS drives.

Unfortunately, I had a little hiccup in that I’d ordered the device pre-configured. The weight of the disks was clearly too much for the plastic drive carriers to cope with but, once again, sorted things out for me and I soon had a replacement in my possession.

Over the last few weeks, I’ve been building up what I’m doing with the Diskstation: providing home drives for the family; syncing all of my cloud storageacting as a VPN endpoint; providing DHCP and DNS services; running anti-virus checks; and backing up key files to Microsoft Azure.

This last workload is worthy of discussion, as it took me a couple of weeks to push my data to the cloud. Setup was fairly straightforward, following Paris Polyzos (@ppolyzos)’s advice to backup Synology NAS data in Microsoft Azure Cool Storage but the volume of data and the network it had to traverse was more problematic.

Initially I had issues with timeouts due to a TP-Link HomeplugAV (powerline Ethernet) device between the ISP router and the DNS server that kept failing. I worked around that by moving DNS onto the NAS, and physically locating the NAS next to the router (bypassing the problematic section of network). Then it was just a case of waiting for my abysmal home Internet connection to cope with multi-GB upstream transfers…

I have no doubts that this NAS, albeit over-specified for a family (because I wanted an Intel-based model), is a great device but I did need to work around some issues with vibration noise. It’s also slightly frustrating that there is no integration between the DHCP and DNS services (I’ve been spoiled working with Windows Server…), the Security Advisor reports are a bit dramatic, and some of the Linux commands are missing – but I really haven’t found anything yet that’s a show-stopper.

Now I need to get back to consolidating data onto the device, and moving more of it into the cloud…

Preventing vibration noise on a Synology NAS

My Synology Diskstation NAS (DS916+) has been a great purchase but I have had some issues with noise from vibration. Over a course of a few weeks, complaints from family members meant that I had to move the NAS from my desk, onto the floor, then into the garage (before I brought it into the kitchen to be next to the Internet connection – but that’s another story). You should be able to hear the noise in the video below (though it seems much louder in real life!):

As can be heard, the vibration noise reduces when I put pressure on the chassis. It seems that it’s actually caused by the screw-less drive carriers that Synology use on their NASs.

Thanks to advice from Chipware on Reddit, I was able to add some sticky-backed Velcro (just the fluffy side) between the disk carrier and the disk, and on the outside of the disk carriers. They now better fit the NAS and, crucially, the Velcro serves as a shock absorber, preventing any more vibrations…

And, at just £2 for a metre of sticky-backed Velcro (which I only used a few centimetres of), it was a pretty inexpensive fix.

Chipware says in his post that:

“I definitely think the 4 Velcro pieces connecting the sled to the cage solved the problem. The pieces between drive and sled connection provides negligible dampening.”

I initially only put 4 pieces on the outside of the carrier (2 of them can be seen in the picture) but my experience was that adding 2 more pieces on the disk itself (underneath the carrier) also helped. Of course, your mileage my vary (and any changes you make are at your own risk – I’m not responsible for any problems it may cause).

After making these modifications there’s no more noise, just a relatively quiet fan noise (as to be expected) and the NAS is back on my desk!