Intro When a program is compiled (and linked) it will no longer contains readable lines of code. Instead it will consist of opcodes (operation codes). I would like to see whether I can find out what dome opcodes mean. You might say “just look at the intel or AMD manual and there you go”…but where […]
Continue Readingsar usage
I like to use the linux utility sar (system activity reporter (?)) I gives a fast and quite complete overview over the performance of a linux system. SAR has a lot of possibilitys. I just highlight a few of them to remember how the syntax is 🙂 CPU information of today oracle@lqas4342:~$sar Linux 4.18.0-425.13.1.el8_7.x86_64 (lqas4342.mod.nl) […]
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Just a write up of the filters I sometimes use/need. (work in progress…) Filtering _out_ ssh: tcpdump “port ! ssh” Just seeing ICMP packets: tcpdump “icmp” Filtering on port _and_ host: tcpdump “port ssh && host host-name”
Continue Readingansible reboot after updating packages
When installing security/kernel packages the system must be rebooted. It would be a bit silly to reboot always. So..without further ado…you can solve this for example with the following playbook: [martijn@fedora basis]$ cat update_all.yaml — – name: Update alle hosts hosts: all become: true tasks: – name: install dnf tools dnf: state: present name: dnf-utils […]
Continue Readingvi beep
I’m was going crazy because off the annoying bell sound vi(m) makes all the time. To solve it I put “set belloff=all” in my .vimrc martijn@radijs:~$ cat .vimrc set belloff=all martijn@radijs:~$
Continue ReadingDIG
Whenever I need to do something concerning DNS resolving I resort to dig. Some examples: Getting the IP adres for maboc.nl: martijnmbos@penguin:~$ dig maboc.nl ; DiG 9.11.5-P4-5.1+deb10u3-Debian maboc.nl ;; global options: +cmd ;; Got answer: ;; ->>HEADERHEADERHEADERHEADER
Continue ReadingEmacs shortcuts
My most used emacs short-cuts: Alt – v : Scroll page up Ctrl – v : Scroll page down Ctrl – k : cut line into the yank buffer Ctrl – y : Yank line(s) (paste yank buffer) Ctrl – a : Move to the start of a line Ctrl – e : Move to […]
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