Archives: Linux



socat introduction No ratings yet.

While searching a command line to write something into a UNIX Domain Socket, I found this great tool called socat which is similar to netcat/samplicator but has more features. The man page said: Socat is a command line based utility that establishes two bidirectional byte streams and transfers data between them. Because the streams can • Read More »



systemctl cheatsheat No ratings yet.

  Systemd template and instance (@) from: https://wiki.archlinux.org/index.php/systemd Note: Some unit names contain an @ sign (e.g. name@string.service): this means that they are instances of a template unit, whose actual file name does not contain the string part (e.g. name@.service). string is called the instance identifier, and is similar to an argument that is passed • Read More »



lxc /dev increased from 100k to 500k and some other minor issues No ratings yet.

While using lxc container, one annoying thing is the disk size of /dev was limited to 100k by default, with some hardware ( with lxc.autodev=1), the /dev could go beyond 100k. discussed on the github: https://github.com/lxc/lxc/issues/781, followed the suggestion from Stéphane Graber (stgraber) I submitted the patch to increase the /dev is to 500k ( though • Read More »


what is application container, OS container , VM No ratings yet.

Application container: docker OS containers: LXC, OpenVZ, Linux VServer, BSD Jails, Solaris Zones VM: KVM, VMware, VirtualBox Good images from https://blog.risingstack.com/operating-system-containers-vs-application-containers/ References https://blog.risingstack.com/operating-system-containers-vs-application-containers/ http://www.itworld.com/article/2915530/virtualization/containers-vs-virtual-machines-how-to-tell-which-is-the-right-choice-for-your-enterprise.html https://www.flockport.com/supercharge-lxc-with-btrfs/   Please rate this rating


Linux device driver: A fix for insmod invalid module format No ratings yet.

How to fix “insmod invalid module format” for a out-of-tree linux device driver or kernel module? If your kernel source tree matched your run time kernel, it turns out that it can be easily fixed by on debian 8: cp /usr/src/linux-headers-3.16.0-4-amd64/Module.symvers /usr/src/linux then make More step by step details on debian 8: (1) setup a • Read More »


convert PDF 1.1 to other versions No ratings yet.

Someone asked me to convert pdf 1.1 to 1.4,  I googled around, and found this: http://stackoverflow.com/questions/3450616/convert-pdf-from-version-1-1-to-1-4-or-higher Pdf 1.1 is forward compatible with pdf 1.4. Everything in pdf 1.1 will work with pdf 1.4 – it’s guaranteed by the spec. Let’s assume that you’ve got some justifiable reason why this is not good enough for you • Read More »