Bullseye, HDMI and out of sync sound

Watching a video with Firefox on Debian Bullseye via an HDMI display and the sound keeps getting out of sync? Booting with


helped me. See #867548.

Minikube, Podman and Proxy

Running minikube behind a proxy with podman? Setup all http_proxy environment variables and podman still won’t use your proxy?

Configuring sudo to heep this variables:

Defaults        env_keep += "http_proxy https_proxy ftp_proxy no_proxy HTTP_PROXY HTTPS_PROXY"

worked for me.

Trigger Jenkins SCM polling

Want to trigger SCM polling for a certain job? Use

Jenkins.instance.getAllItems( Job.class ).
  find { job -> job.fullName == 'p1' }.
  each { job ->

nc10, root on luks, modules=dep and missing cipher

Trying to boot debian buster on a Samsung nc10 with crypted root? Getting

Check that kernel supports aes-xts-plain64 cipher

when you switch initramfs to modules=dep?

Adding ecb to /etc/initramfs-tools/modules and running update-initramfs -k all -u worked for me.

Nextcloud, Collabora and 404s

Running your own docker based Collabora Online server? Getting 404s after an update with these log entries:


Seems like some URLs where changed:

Seems like /loleaflet has been renamed to /browser and lool to cool in latest collabora version.

See #1904 and Proxy Settings.

MariaDB and lost+found

Having /var/lib/mysql on a separate partition? MariaDB thinks lost+found is a Database? Create /etc/mysql/conf.d/ignore.cnf with


Restart MariaDB and drop the database:

drop database `lost+found`;

Focal and Black Screen

Performing a minimal Ubuntu 20.04 install on a server? Black screen after rebooting? Switch to console via ALT+F1 and change in /etc/default/grub


Run update-grub and reboot.

Powershell and Certificate Chain

On Windows, and need to generate a certificate chain to a server? This script creates one file per certificate in the chain:

$destination = 'foo'

$webRequest = [Net.WebRequest]::Create(https:// + $destination)
$webRequest.AllowAutoRedirect = $FALSE
$webRequest.Method = 'HEAD'
$webRequest.Timeout = 1000

try {
    "Connecting to $destination... " | Write-Host -NoNewline
    $webRequest.GetResponse().HResult | Write-Host
catch [System.Net.WebException] {
    $_.Exception.Status | Write-Host

    if ( $_.Exception.Status -ne 'Timeout' ) {
        throw $_

"Building certificate chain..." | Write-Host
$chain = New-Object -TypeName System.Security.Cryptography.X509Certificates.X509Chain
$chain.build( $webRequest.ServicePoint.Certificate ) | Out-Null

$contentType = [Security.Cryptography.X509Certificates.X509ContentType]::Cert

"Saving..." | Write-Host
# Skip server certificate
$chain.ChainElements.Certificate | Select-Object -Skip 1 | ForEach-Object {
    set-content `
        -value $( $_.Export( $contentType  ) ) `
        -path "$pwd\$( $_.Thumbprint ).cer" `
        -encoding byte

} | Format-Table | Out-String | Write-Host

FreeIPA, Firefox and SSL

Playing with FreeIPA? Recreating the CA? Firefox complaining about SEC_ERROR_REUSED_ISSUER_AND_SERIAL? Can’t find the certificate via Preferences / Privacy & Security / Certificates?

Try deleting it via CLI:

certutil -L -d <folder/to/cert8.db> | grep -i ipa
certutil -D -d <folder/to/cert8.db> -n <nickname>