People routinely talk about self signed TLS certificates. You usethem in situations where you just need TLS but don't want to setup an internal Certificate Authority and can't get an official TLScertificate, and many CA root certificates are self signed. Butuntil recently I hadn't thought about what a self signed certificateis, mechanically. So here is my best answer.

To simplify a lot, a TLS certificate is a bundle of attributes wrappedaround a public key. All TLS certificates are signed by

Marc Booker's Code Only Says What it Does ( via ) is aboutwhat code doesn't say and why all of those things matter. BecauseI want you to read the article, I'm going to quote all of the firstparagraph:

Code says what it does. That's important for the computer, becausecode is the way that we ask the computer to do something. It's OK forhumans, as long as we never have to modify or debug the code. As soon

At the moment, the most recent things I've seen have talked about us not returning to the officebefore September, and then not all of us at one time. This givesme complicated feelings, including about what work we are doing.From the outside, our current work from home situation probablylooks like everything is going pretty well. We've kept the computinglights on, things are being done, and so far all of the ordinarythings that people ask of us get done as promptly as usual

One of the issues we sometimes run into with ZFS is that ZFSessentially requires you to reflect your administrative structurefor allocating and reserving space in how you lay out ZFS filesystemsand filesystem hierarchies. This is because in ZFS, all spacemanagement is handled through the hierarchy of filesystems (andperhaps in having multiple pools). If you want to make two separateamounts of space available to two separate sets of filesystems (orcollectively reserved by them), either they must be in differentpools or they must be under different

When ZFS was new, the only option it had for filesystems quotas wasthe quota property, which I had an issue with and which caused us practical problems in our first generationof ZFS fileservers because it covered the spaceused by snapshots as well as the regular user accessible filesystem.Later ZFS introduced the refquota property, which did not havethat problem but in exchange doesn't apply to any descendant datasets(regardless of whether they're snapshots or regular filesystems).At one level this issue with refquota is fine

We have a Django web application to handle (Unix) account requests , which is now nine years old. I've calledthis utility code , but I mentioned recently that over that time therehave been some changes in how graduate students were handled thatneeded some changes in the application. Except not very much changewas necessary, in some ways, and in other ways the changes arehacks. So here are some stories of those changes.

When we (I) initially wrote the web application, our model of

The last time around I talked about what Blackbox's TLS certificateexpiry metrics are checking , but itwas all somewhat abstract. The recent AddTrust root expiry provides a great example to make it concrete. As a quick summary,the Blackbox exporter provides two metrics, probe_ssl_earliest_cert_expiry for theearliest expiring certificate andprobe_ssl_last_chain_expiry_timestamp_seconds for the latestexpiring verified chain of certificates.

If your TLS server included the expiring AddTrust root certificateas one

A while back I wrote about how Django's goals are probably notour goals for our web application , but atthe time, I didn't have a succinct way of talking about why this wasthe case. Recently I wrote about a realization I'd come to about product code and utility code ,where product code is used as part of delivering your business bututility code sits in the background doing other things. Thatrealization gives me a better way to talk about Django and us.

Right from its

I recently tweeted a wish for NetworkManager :

I wish there was some straightforward way to tell NetworkManager tonot automatically connect to any wifi networks if my laptop has awired network connection, while still auto-connecting if there is nowired Ethernet.

In NetworkManager you can set a priority for network connections,but as far as I can tell you can't tell it that two connectionsconflict with each other and should never be brought up at the sametime. You can write scripts that run when connections change andthat