Linux

After removing a Mailman list, HyperKitty, the mail list archive manager, starts using all available CPU time. What’s going on?

Awk and Gawk are very powerful tools to process text files. Yet, CSV files are especially difficult to process. Fields are separated by comma or semicolon, depending on the country. These separators can also be used in a field inside double quotes. Which makes it very difficult for Awk to split a line into fields. Moreover, a field with double quotes can contain line breaks, which makes it difficult for Awk to process it.

On Linux, resources limits are there to ensure that a single user will not saturate the server resources. These limits can cause silent failures. The best way to detect these failures is to use the auditd daemon, which can catch the result of individual system calls.

On Internet, some sites might be mysteriously unreachable while the server hosting the site is alive and well. What is the cause of these mysterious black holes.