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Test Methodology for Percona TDE Performance Test

This blog posting has a detailed explanation how the TDE performance test was conducted.

Performance Test for Percona Transparent Data Encryption (TDE)

This blog posting compares the performance of the pg_tde by Percona extension for PostgreSQL with the performance of an unmodified PostgreSQL. The pg_tde by Percona extension provides encryption for both data pages on disk as well as WAL files on disk - Encryption at Rest.

certbot on Debian Bookworm fails with: The peer didn't know the key we used

Was setting up a new Debian Bookworm system in my home environment. So far I was not using certificates at home, and wanted to change this along the way, using Let's Encrypt. Since the IP-addresses here are RFC1918, I can't use the http01 challenge, and have to resort to dns01 challenges. On Debian Bookworm, using certbot, this fails reproducible.

Watch for changed files in SyncThing

For syncing files between my devices I'm using SyncThing. This tool is reliable, available on Linux, Android, Mac and iOS. And it encrypts the communication. But sometimes I want to know when files in certain directories have changed - as example in my Obsidian vault. This allows me to post-process the files.

Migrate Maildir to Gmail

Recently it was time to refurbish our email infrastructure. For a very long time I was hosting everything for myself, but things don’t get easier and over time even the spam filters couldn’t catch up. Therefore I looked into a number of hosted services, and in the end settled with Google Gmail.

End of last year I ran a test, migrated one of my domains over to Gmail and tried out if Gmail offers all the required functionality. As with every change, not everything works flawlessy, but mostly I found ways to get things working. As example we have different domains, several users, multiple identities (one per domain), other servers (like a webserver) can create emails as well (needs to play well with SPF and DKIM), a number of different email programs, mobile support and more.


mutt, encrypted emails and your mail storage

Like a few other people, I occasionally (very occasionally) receive encrypted emails. So far that was not a big deal, because mutt can automatically decrypt these emails, and also search in encrypted emails (by decrypting them first). However I plan to change my email setup in the near future, and allow other programs (like Thunderbird or a mobile client) access as well. This does not work well if the emails are still encrypted. Besides, the emails reside on an encrypted filesystem, there is no need for another layer of encryption on disk.


Thunderbird, Enigmail and sending encrypted mails as attachment

By default, the OpenPGP extension in Thunderbird (Enigmail) sends every encrypted mail as inline text, not as an attachment. Mutt as example does not recognize the encrypted mail but just displays the unreadable binary stuff.


MUA changed

Finally, after (I think) 13 years, I switched my mail user agent from pine to mutt. Not that I like the latter more, it has other problems and/or ways of handling mails which I don’t like. But the (non-existent) pgp support in pine drove me crazy. After configuring a while around, more than 300 .muttrc config lines and some Perl scripts to create send-hooks from nicely configured roles later, I have almost the same behaviour like before.