--- /dev/null
+Using pm-utils to save/restore VMs on workstation suspend/restore
+#################################################################
+
+:date: 2017-09-16
+:tags: hints,ubuntu,vagrant,pm
+:category: hints
+:author: Jude N
+
+I use Ubuntu (16.04 for now) and Vagrant (1.9.0 for now) on a bunch of my projects, and I've been running into somethinng like this
+`power management bug` for a while now, where after restoring from suspension, my vagrant sessions would be dead and I'd have to
+'vagrant halt' and 'vagrant up' before another 'vagrant ssh' would succeed.
+
+To work around this, I came up with some /etc/pm/sleep.d scripts which would save any running vagrant boxes when suspending the
+workstation and then resume the VMs when resuming the workstation.
+
+Now if I'm in a 'vagrant ssh' session and Ubuntu suspends/resumes, instead of coming back to a frozen session, I'll see I've been
+disconnected from the ssh session, and I can do another 'vagrant ssh' without having to halt/re-up the VM. That's better than nothing,
+but the next step here is to start using something like screen or tmux in my vagrant sessions so I can restore right back to where I left
+off.
+
+So why bother with two scripts when you could have 1 script with a single case statement ? I wanted saving the running vagrant boxes to
+happen when all the usual services and userspace infrastructure was still running, so I wanted that script in the 00 -49 range from as
+per the 'Sleep Hook Ordering Convention' portion of 'man 8 pm-action`. However I don't restoration to happen until all the services
+restarted, so I pushed to the end of the service handling hook range. I may want to revisit this, and rename it to 75_vagrant.
+
+Note in the resume script, the command is pushed into the background since I didn't want want to wait for the VMs to be restored before
+resuming Ubuntu. I'm usually checking email or the web for a bit before going back to my VMs so I'm OK if that's ready immediately.
+
+Here are some other lessons I learned from these scripts:
+
+- I didn't know `vagrant global-status`_ existed !
+- vagrant commands have to be run as the user started the VM. I had to use runuser to run the vagrant commands as my dev user.
+- I learned the '-I %' approach of `getting xargs to insert it's argument in the middle of a command`_.
+
+The first script is /etc/pm/sleep.d/01_vagrant:
+
+.. code-block:: bash
+
+ #!/bin/bash
+
+ YOURNAME="your normal nonroot user name"
+
+ case "$1" in
+ suspend)
+ timestamp=`date --rfc-3339=seconds`
+ echo "${timestamp}: $0 output" >> /var/log/pm-suspend-vagrant.log
+ (/sbin/runuser -u ${YOURNAME} /usr/bin/vagrant global-status | grep running | awk '{ print $1; }' | xargs -L1 -I % runuser -u ${YOURNAME} vagrant suspend % ) >> /var/log/pm-suspend-vagrant.log
+ ;;
+ *)
+ ;;
+ esac
+
+ # Don't let errors above stop suspension
+ true
+
+The second script is /etc/pm/sleep.d/74_vagrant.sh
+
+.. code-block:: bash
+
+ #!/bin/bash
+
+ YOURNAME="your normal nonroot user name"
+
+ case "$1" in
+ resume)
+ # Push the restoration into the background so it doesn't slow down
+ timestamp=`date --rfc-3339=seconds`
+ ((/sbin/runuser -u ${YOURNAME} /usr/bin/vagrant global-status | grep saved | awk '{ print $1; }' | xargs -L1 -I % runuser -u ${YOURNAME} vagrant resume % ) >> /var/log/pm-resume-vagrant.log) &
+ ;;
+ *)
+ ;;
+ esac
+
+ # Don't let errors above stop restoration
+ true
+
+Sources:
+- http://manpages.ubuntu.com/manpages/xenial/man8/pm-action.8.html
+
+.. _power management bug: https://www.virtualbox.org/ticket/15378
+.. _vagrant global-status: https://www.vagrantup.com/docs/cli/global-status.html
+.. _getting xargs to insert it's argument in the middle of a command: https://stackoverflow.com/a/40355248/496127
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