Archive for February, 2022

My ability to control the future (humor)

Tuesday, February 22nd, 2022

So, occasionally I find my ability to control the future amusing. I’ve stopped transacting in bitcoin because I find the amount of power that it uses unacceptable and the lack of evolution of the bitcoin network distressing. However, I still have some bitcoin. If I were to sell this bitcoin, the future value of bitcoin would exceed $1m/BTC – after I sold it, of course. If I HODL it for the rest of my life, the future value of bitcoin will asymptotically approach zero.

RabbitMQ websocket URL wrong in documentation

Monday, February 21st, 2022

Just sticking this here in the hopes that it will get listed in google and maybe save some folks a little time.

If you are trying to use rabbitMQ’s websocket STOMP connector, as discussed on https://www.rabbitmq.com/stomp.html, be aware that the URL given in the documentation on this page is wrong (or perhaps only applies to newer versions of rabbitmq).

The correct way to successfully create a websocket to RabbitMQ 3.5.7 (which ships with Ubuntu 16.04) is as follows:


var ws = new WebSocket(‘ws://yourhostname:15674/stomp/websocket’);
var client = Stomp.over(ws);

Later note: The documentation is correct for newer versions of RabbitMQ.

Sheer quote on racism

Wednesday, February 16th, 2022

I posted this on facebook, but it occured to me it might be worth saving here

“Seeking a middle ground in racial politics, given that one side is nazis, is a little like seeking a middle ground between closed and open on a circuit breaker. It might exist (in the sense that briefly the contacts are in transition and there’s a arc drawn between them) but if you stay there too long shit is probably going to catch on fire and someone is going to get hurt. Some things really are black and white, and I am mystified as to how you can find middle ground between “I want to kill people who are a different race than I am” and “everyone is the same under the skin”.”

Dell 7810 No Video issue

Tuesday, February 15th, 2022

So, I’ve been buying Dell 7810s for my kitten trader 3.0 cluster, and I thought I’d somehow gotten three bad ones from two vendors. No, actually, Dell thoughtfully stores the slot that the video card is in in the BIOS! Changing the video card for another model results in no video – so, if you have a 7810 that you’ve put a new video card in that won’t display anything, the trick is to remove the battery, short the two pins that would have been the battery together, then power it on – the display will, after about 45 seconds (be patient) and one uncommanded power cycle actually light up with the dell logo and a option to push F2 to enter setup – *immediately* go into setup and select the slot # the card is in under ‘video’. (There will be a helpful hint listing video card type on every slot with a detected video card). It will tell you that on systems with a single video card you can select ‘auto’ but as far as I can tell, this is a lie, or maybe is only true if you use only Dell-approved video cards. If you don’t save this setting the next time you boot you will again have no video.

Most of these systems are destinated to be headless for me anyway so I really only need video long enough to configure them, but it’s still a great help. I hope this helps someone else in the same kettle of fish I was in as it took me 2 hours to figure this out.

Setting a static IP on ubuntu 20.04 with cloud-init

Friday, February 11th, 2022

So, it took me numerous tries, digging, and beating of head against curtin and the like, but I have finally figured out how to set a static IP on a host using cloud-init.

Mind you, I am not talking about setting a static iP for while the installer is running. That’s easy, and well documented. I’m talking about the next time it boots.

The solution requires two bits. They’re pretty straightforward, and both go in the cloud-init file

Bit one goes at the end of the autoinstall section, and deletes the default configuration and writes a permanent one instead. Note that the filesystem is mounted as /target


late-commands:
– rm /target/etc/cloud/cloud.cfg.d/50-curtin-networking.cfg
– mv /tmp/00-installer-config.yaml /target/etc/netplan

Bit two actually writes out the /tmp/00-installer-config.yaml that late-commands will be editing


write_files:
– path: /tmp/00-installer-config.yaml
owner: root:root
permissions: “0644”
content: |
network:
version: 2
ethernets:
ens160:
critical: true
dhcp-identifier: mac
dhcp4: true
ens192:
dhcp4: no
addresses:
– {ipaddr}/16
gateway4: 172.16.1.1
nameservers:
addresses:
– 172.16.5.6
search:
– search.domain