Installing Docker on Ubuntu Quick Fix

Posted on 4th September 2014 by Alex Galbraith | Permalink Comments Off on Installing Docker on Ubuntu Quick Fix

I was installing Docker on Ubuntu (14.04.1 LTS) in my home lab for the first time following the instructions at http://docs.docker.com/installation/ubuntulinux/ this evening and came across an issue.

Docker would not start and was showing the following error:

Cannot connect to the Docker daemon. Is 'docker -d' running on this host?


Checking processes I don’t see docker running:

$ ps -ef | grep docker
alex      3703  2113  0 21:27 pts/0    00:00:00 grep --color=auto docker


Trying to start docker generated the following errors in /var/log/syslog:

kernel: [  608.236848] init: docker main process ended, respawning
kernel: [  608.451873] init: docker main process (4230) terminated with status 1
kernel: [  608.451906] init: docker main process ended, respawning
kernel: [  608.676417] init: docker main process (4280) terminated with status 1
kernel: [  608.676445] init: docker respawning too fast, stopped


After trying a bunch of different fixes which didn’t work, then looked up the docker log at /var/log/upstart/docker.log, which displayed the following:

Error loading docker apparmor profile: fork/exec/sbin/apparmor_parser: no such file or directory ()


A quick install of apparmor fixed this!

$ sudo apt-get install apparmor


And now…

$ ps -ef | grep docker
root      4577     1  0 21:44 ?        00:00:00 /usr/bin/docker -d
alex      4608  2574  0 21:45 pts/0    00:00:00 grep --color=auto docker
$ sudo docker info
Containers: 0
Images: 0
Storage Driver: devicemapper
 Pool Name: docker-8:1-156936-pool
 Pool Blocksize: 64 Kb
 Data file: /var/lib/docker/devicemapper/devicemapper/data
 Metadata file: /var/lib/docker/devicemapper/devicemapper/metadata
 Data Space Used: 291.5 Mb
 Data Space Total: 102400.0 Mb
 Metadata Space Used: 0.7 Mb
 Metadata Space Total: 2048.0 Mb
Execution Driver: native-0.2
Kernel Version: 3.13.0-35-generic
Operating System: Ubuntu 14.04.1 LTS


Happy Days! I hope this saves others some time!

If you found this post useful, check out my Docker HOWTO series – the first post is here:
http://tekhead.it/blog/2014/09/docker-part-1-introduction-and-howto-install-docker-on-ubuntu-14-04-lts/

Docker , , , , ,

Cannot See Any iSCSI Devices on Synology from a vSphere Host

Posted on 1st September 2014 by Alex Galbraith | Permalink Comments Off on Cannot See Any iSCSI Devices on Synology from a vSphere Host

Just a quick fix I discovered this weekend. It’s probably quite specific but hopefully if you come across this in future it will save you some time.

I had just finished rebuilding the second node in my lab from 5.1 with a fresh install. I added the software iSCSI initiator and connected it to my iSCSI target (Synology DS412+) using Dynamic Discovery. I then rescanned for a list of devices, and although I was picking up the IQN for the iSCSI server, I couldn’t see any devices!

I tried lots of things including removing and re-adding the initiator, messing with iSCSI bindings, but nothing! Very frustrating.

After a bit of googlage, I came across this KB article from VMware:

Cannot see some or all storage devices in VMware vCenter Server or VirtualCenter (1016222)

Although this was specific to VI3/vSphere 4, it did trigger a thought! Just before I built the new node, I rejigged all of my storage LUNs, deleting 3 old ones in the process (which just so happened to be the first 3 LUNs on my NAS). What I believe this caused is that the LUNs were viewed by node 1 as different LUN IDs on node 2, so they refused to show up!

So now, the fix. Incredibly simple as it turns out:

  1. Created three new temp 10GB LUNs on my old NAS which would then assume LUN IDs 1/2/3 as they originally had (before I deleted them).
  2. Rescan the new node of the cluster for storage
  3. Confirmed all of the LUNs are now visible
  4. Deleted the three temp LUNs from the Synology (I don’t plan to add any more nodes for now so I have no need of these temp LUNs, but as they’re thin provisioned anyway it actually wouldn’t hurt to leave them there).
  5. Rescan the ESXi host again to ensure it can still see the LUNs.
  6. Job done!

Synology iSCSI Devices

Not much to it, but worth a quick post I thought as this simple issue wasted a chunk of my time!

VMware , , , , , , , , , , , ,

EVO:RAIL / EVO:RACK – Key Blog Posts

Posted on 25th August 2014 by Alex Galbraith | Permalink Comments Off on EVO:RAIL / EVO:RACK – Key Blog Posts

So apparently VMware have announced something new today… You could hardly tell from the 3,000,000 tweets, but apparently it’s causing quite a stir!

Anyway, rather than repeat what many others have already said, I thought I would collate all of the main blog posts relating to this exciting new product.

I for one am looking forward to playing with this at the Hands on Labs in VMworld Barcelona in October!

VMware Official Posts

Mike Laverick (Part VMware / Part vBlogger) 🙂

vBloggers

The Register

Vendors

Hands on Labs

I will update the above list as more posts come out!

VMware , , , , , , , , , ,

My Synology DSM Blue LED issue was actually just a failed drive!

Posted on 24th August 2014 by Alex Galbraith | Permalink Comments Off on My Synology DSM Blue LED issue was actually just a failed drive!

This weekend I spent several hours trying to resolve an issue with my Synology DS413j which I use for backing up my other two Synology hosts (DS412+).

I was experiencing many of the symptoms in the following post, yet I was convinced I could not have been hacked, as this server is not available to the internet! Not only that but I recently updated DSM (2-3 weeks ago) so wondered if this could be the cause?…

http://forum.synology.com/enu/viewtopic.php?f=108&t=82141

After following the full 11 step fix (minus the migratable step as it wouldn’t work), I still had a box which was unresponsive. My symptoms were:

  • Power LED light blinks blue
  • I could not log into the DSM console
  • DSM login simply says “Processing, please wait” forever or eventually times out
  • I was able to ping DSM
  • I could not reset DSM using the reset button on the back of the device
  • Booting of the device took a very long time (up to 20 mins) and Synology Assistant shows “Starting Services…” for a very long time
  • Even after following rebuild steps I could not get the Synology Assistant to show “Migratable”
  • Once booted I could see the SMB shares and access them intermittently

After much head scratching I decided to take each of the drives in turn and test them on my Windows desktop. I have 4 drives in the host, 2x Seagate and 2x WD Red. If any of them were going to fail I believed the Seagate would be at fault, so I tested those first. I plugged in disk number one, ran some tests, all ok. I then plugged in disk number two, and discovered that windows would not even mount the drive. Not only that but it was actually causing device manager to hang.

Faulty drive identified, I powered on the Synology with the remaining 3 drives only. Much to my relief, the system booted within a minute and started to beep, warning me I was missing a drive. DSM is now responding just fine.

I have now ordered a new WD Red drive to replace the failed Seagate (which was out of its very short warranty of course!).

Moral of the story: If your box looks like it may have been hit by SynoLocker but it was never on the internet, try testing all the drives in turn. You may just save yourself a few hours / days of pain!

One other wee tip is to also enable SSH access. I’m not sure if I could have logged in via SSH in the hung state, but it may have given me another troubleshooting avenue.

Synology , , , , , , , , , ,