The other day, I had the need to look closer into the network communication of a (dockerized) JEE application. My usual tcpdump approach wasn’t applicable though because the traffic was TLS-encrypted.Finally, I ended up with a setup where the app used a man-in-the-middle proxy for all its communication - that proxy transparently re-encrypted the traffic which gave me the chance to inspect every single message exchanged. ...
Over years JMeter has always been a valuable tool in my box when dealing with performance testing. But when we’ve integrated those tests with our CI/CD-pipeline we always had hard times to control the pipeline outcome based on the performance results. In other words, let the test results act as a quality gate for either promoting the build-artfiact along the pipeline or not. ...
Cheatsheet for Linux User Management Handling users # adds a new user called 'schoeffm' useradd -m -s /bin/zsh -G docker schoeffm # └┬┘└────┬─────┘└─┬─────┘ # │ │ │ # │ │ └─> List of groups the user # │ │ should be a member of # │ └─> login shell of the new account # └────────> also create a home directory for this # account # Assigns a new UID to <─────┐ # this account │ # ┌──┴──┐ usermod -aG docker -s /bin/zsh -L|U -u 4711 schoeffm # └───┬────┘ └───┬─────┘ └─┬─┘ # │ │ └─> Lock or Unlock user # │ └─> set new login shell for account # └────────────> append to the list of groups # without 'a' this will replace # the group list userdel not explicitly shown here since it’s comprehensible....
Cheatsheet for Linux Permission Management Standard Permissions There are three basic permissions which are read, write and execute. And they can be granted to a specific user (so if you are not that user those permissions do not apply to you) a group of users (if you’re not a member of that group those permissions do not apply to you) to all other users (so if the first two do not apply - these are then the permissions you’ll have on the respective file/directory) This is also the order in which linux checks the permissions....
When debugging network related issues the CLI tool tcpdump is a valuable assistant. I usually use a variation of this base command: sudo tcpdump -A -i lo0 -n -s0 -v port 8080...
Dealing with SSH-connections can become cumbersome quickly especially when configurations change frequently, too. Luckily, you can pre-configure most of a connections settings in a user specific config-file located in your ~/.ssh-folder called config. ...