(February 2020 onwards) WMT Pi VMs

[hamishmb]

Please note, you may wish to enable the "Use Host I/O Cache" option for each storage controller when using these VMs.

This option queues disk writes and reads for better performance. On SSDs it should be okay either way, but I have found on the HDD I've been keeping the VMs on, performance is abominable without that option turned on. In due course, I guess when we update the VMs at some point, we can fix this so that no one has to remember to enable this option.

[hamishmb]

Okay, today I updated the WMT VMs. They are still available in the same location - see first post.

Changes:

• Installed system updates.
• Enabled Host I/O Cache - massively improves performance when run on HDDs.
• Installed git (makes it easier to deploy and update the river system software).
  • Tracks the master branch - just run "git pull origin master" to update.
• Enable autologin in the base image.
  • Previously done for each individual VM, end user sees no difference here, but easier to maintain.
• Enable passwordless sudo.
  • This is what Raspbian uses.
  • Instructions I used are at: https://serverfault.com/questions/16058 ... o-on-linux, and coming soon to the installation spec.
• Installed xinetd on base image.
  • Used to sync time with NAS box VM and Sump Pi (fallback).
  • Installed in base image for convenience, unused on other pis.
• Install net-tools package (provides ifconfig as on Raspbian).
• Install current (as of this post) version of river control system software.
• Added VMs for Hanham Pis.
• Created fake temperature_monitor script for NAS box VM.

Notes:

• The NAS box VM is now based on the river system base image, so the download is a lot smaller.
• The engineer GUI isn't present on the NAS box VM because the PHP version (and extensions) are not compatible with those in the NAS box.
  • phpMyAdmin can be used instead to monitor the tables.
• The Gate Valves labelled VALVE6 and higher will currently fail with an "invalid system ID" error, as these are not yet enabled in config.py

Currently waiting for Patrick to test they work on his end too, but should be fine.

[hamishmb]

Terry, do you recall if I updated the installation spec to include these changes? I need to rebuild some of the VMs because I messed the network configuration up.

[TerryJC]

Terry, do you recall if I updated the installation spec to include these changes? I need to rebuild some of the VMs because I messed the network configuration up.

I think you must have, because the version on the fileserver is dated 24th August, which is two days after the above posting. The trouble is I can't find where you shared the updated version with me.

[hamishmb]

Hmm, I wouldn't have done that without checking it with you. Perhaps in an old email?

I'm looking at you, Google Search that still isn't working

[TerryJC]

Hmm, I wouldn't have done that without checking it with you. Perhaps in an old email?

I'm looking at you, Google Search that still isn't working

I've found it! You uploaded your version to the Installation Specification Topic in the Design forum on 24th Aug viewtopic.php?p=4024#p4024.

So it looks as if the one on the fileserver is up to date.

I don't think Google is going to cut it.

[hamishmb]

Excellent, I'll sort the VMs out next week if time and patience permit - it's not the most exciting job ever, suffice it to say.

Yeah, the Google thing clearly isn't going to work. I'll come up with a new idea.

[hamishmb]

I have issued a minor update to the VMs that changes the following:

• River system software updated to latest version.
• Network configuration fixed for all VMs so using git to update the software works properly now.
• Updates installed.
• Valve pis now have the proper system ID in their name eg "VALVE4" instead of "V4".

I am uploading these new VMs now, and have uploaded an updated draft of the installation spec to the relevant topic.

[hamishmb]

NB: VMs updated to use relative paths to the HDDs, so people other than me can use them (oops!).

[PatrickW]

I have tested the VM creation instructions in Installation Specification Iss 0.14. The technical side of it seems mostly fine to me.

I did stumble over the instructions a bit. So, I have produced an updated draft. (See the Installation Specification thread.)

I've only a couple of questions that relate to the actual process of creating VMs:

Is it necessary to specify version 2.0.1 for mysqlclient? If so, why? It's not explained. And should this also be specified when installing on real hardware, under 4.4.2.2.1? Currently the instructions for creating VMs say first to follow the instructions in section 4.4.2.2.1 (which tell you to install mysqlclient without specifying a version) and then they say to install mysqlclient at version 2.0.1. pip3 is happy to downgrade the version if you have already installed a later one, but I didn't know why I needed version 2.0.1.

I've assumed that the intention of your changes relating to xinetd was to install xinetd on the base image, but to only configure it to be enabled on sumppi. Therefore, in my draft new version of the text, I've kept the instructions for installing it in the base image section, but I have moved the instructions for enabling it into the section for the individual VMs. Is that correct?