Systemd doesn’t completely control whether core dumps are made or not. It mainly determine where such dumps go, and whether they should take up space or not. It may prevent some user space core dumps, but not all. With “Storage=none”, they can still occur and are registered by journald, but they don’t take up disk… Read More: Disable core dumps in #Linux »
In a lot of multi-language enterprise applications where you have to support labels in different languages the text files with the different labels for each language are scattered across your source code. In my case I all the labels are kept in Java property files with “.properties” file extension. Then for each language I have… Read More: Convert text label files to UTF-8 encoding »
Reinstalling things like Oracle is always a hassle and takes about one day to make it work. Lucky for me I made a full back-up of my old disk when I upgraded to a new laptop. On the new laptop I did a fresh install of Fedora 28. The idea is to migrate my old… Read More: Recover an #Oracle installation from a full disk backup in… »
Generation of core dumps that result in freezing the Linux system is another common issue in the new Linux kernels discussed on many forum threads. Same as the bug of kswapd0 discussed here Kswapd0 going haywire this can become very annoying. It seems that lately someone tries to add developer features turned on by default… Read More: Disable core dump generation on #Linux »
I like when solutions you are excited about and are first seen as “experimental” start to go mainstream. This happened with containers (Docker, CoreOS, Kubernetes etc.) which are now the hottest topic in DevOps right now. The same is happening now for Apache Kafka which was adopted by no other than “Goldman Sachs” for their… Read More: #Apache #Kafka solutions going mainstream »
This is a common issue in the new Linux kernels discussed on many forum threads. There is a long thread here about this problem. In short the issue is that when you run out of memory “kswapd0” a kernel process than manages virtual memory will start moving “old memory entries” to swap. The “run out… Read More: A solution for kswapd0 going haywire on #Linux »
As you are aware, no service runs alone on some server. You always have to take into account the communication layer between your server and client services. One of the most tricky thing a lot of people overlook is the “housekeeping” of the communication layer. In a properly setup enterprise environment your communication layer (firewalls,… Read More: TCP keepalive: what is it, why do you need it,… »
Following is a simple and easy way to do a consistent back-up of the /home directory (usually mounted in a separate partition) on a running system. We do not have the luxury of being able to stop the operations of a server and unmount the home partition to make sure no changes are done during… Read More: Back-up of /home of a running system using lv snapshot »
Sometimes really simple questions are hard to answer. One day I got the question from a coworker: “How do I know if some installed RAM is ECC or not”. The easiest way is to use dmidecode command that dumps in Linux all the system characteristics. But because I had no idea how to see if… Read More: Find in Linux if your installed RAM is ECC »
Sometimes you get a CA certificate in DER format and some application requires it in a PEM format. OpenSSL to the rescue: # openssl x509 -inform der -in myCA.der -out myCA.pem