I’ve been setting up a new Proxmox server and messing around with VMs, and wanted to know what kind of useful commands I’m missing out on. Bonus points for a little explainer.

Journalctl | grep -C 10 'foo' was useful for me when I needed to troubleshoot some fstab mount fuckery on boot. It pipes Journalctl (boot logs) into grep to find ‘foo’, and prints 10 lines before and after each instance of ‘foo’.

  • demonsword@lemmy.world
    4·
    17 hours ago

    Something that really improved my life was learn to properly use find, grep, xargs and sed. Besides that, there are these two little ‘hacks’ that are really handy at times…

    1- find out which process is using some local port (i.e. the modern netstat replacement):

    $ ss -ltnp 'sport = :<port-number>'

    2- find out which process is consuming your bandwidth:

    $ sudo nethogs

    • eli@lemmy.world
      1·
      4 hours ago

      You can do “ss -aepni” and that will dump literally everything ss can get its hands on.

      Also, ss can’t find everything, it does have some limitations. I believe ss can only see what the kernel can see(host connections), but tcpdump can see the actual network flow on the network layer side. So incoming, outgoing, hex(?) data in transit, etc.

      I usually try to use ss first for everything since I don’t think it requires sudo access for the majority of its functionality, and if it can’t find something then I bring out sudo tcpdump.

    • Ephera@lemmy.mlEnglish
      2·
      15 hours ago

      I always just do ss -ltnp | grep <port-number>, which filters well enough for my purposes and is a bit easier to remember…