A person with way too many hobbies, but I still continue to learn new things.

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Joined 2 years ago
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Cake day: June 7th, 2023

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  • Agreed on Debian stable. Long ago I tried running servers under Ubuntu… that was all fine until the morning I woke up to find all of the servers offline because a security update had destroyed the network card drivers. Debian has been rock-solid for me for years and buying “commercial support” basically means paying someone else to do google searches for you.

    I don’t know if I’ve ever tried flatpaks, I thought they basically had the same problems as snaps?


  • I’m not sure about other distros, I’ve just heard a lot of complaints about snaps under Ubuntu. Cura was the snap I tried on my system that constantly crashed until I found a .deb package. Now it runs perfectly fine without sucking up a ton of system memory. Thunderbird is managed directly by debian, and firefox-esr is provided by a Mozilla repo so they all get installed directly instead of through 3rd-party software (although I think I tried upgrading Firefox to a snap version once and it was equally unstable). Now I just avoid anything that doesn’t have a direct installer.



  • That’s what I was thinking too… If they’re running Ubuntu then they’re probably installing packages through snaps, and that’s always been the worst experience for me. Those apps lag down my whole system, crash or lock up, and generally are unusable. I run Debian but have run into apps that wanted me to use a snap install. One package I managed to find a direct installer that is rock-solid in comparison to the snap version, and the rest of the programs I abandoned.

    Firefox (since it was mentioned) is one of those things I believe Ubuntu installs as a snap, despite there being a perfectly usable .deb package. I applaud the effort behind snap and others to make a universal installation system, but it is so not there yet and shouldn’t be the default of any distro.



  • But why doesn’t it ever empty the swap space? I’ve been using vm.swappiness=10 and I’ve tried vm.vfs_cache_pressure at 100 and 50. Checking ps I’m not seeing any services that would be idling in the background, so I’m not sure why the system thought it needed to put anything in swap. (And FWIW, I run two servers with identical services that I load balance to, but the other machine has barely used any swap space – which adds to my confusion about the differences).

    Why would I want to reduce the amount of memory in the server? Isn’t all that cache memory being used to help things run smoother and reduce drive I/O?


  • And how does cache space figure in to this? I have a server with 64GB of RAM, of which 46GB is being used by system cache, but I only have 450MB of free memory and 140MB of free swap. The only ‘volatile’ service I have running is slapd which can run in bursts of activity, otherwise the only thing of consequence running is webmin and some VMs which collectively can use up to 24GB (though they actually use about half that) but there’s no reason those should hit swap space. I just don’t get why the swap space is being run dry here.



  • So ldirectord is kind of a front-end for ipvsadm. The tools allow you to set up load-balancing between internal servers. I run each service in a VM, and I have at least two copies of each (on separate physical servers). Ldirectord lets me configure how frequently to verify each machine is up, a list of primary servers, and an optional backup when the others go down. Overall it works pretty smooth.

    Shorewall is similarly a front end for iptables, allowing a more structured set of configuration files. I’ve been trying to start using Webmin for the first time because it has some nice management of shorewall, maybe I’ll be able to clean up some of my config, but I’d also like to get traffic shaping configured.

    I have a dedicated firewall (just moved to a poweredge R620 last night), a NAS, and two VM systems to run services on… all run from home. I enjoy setting things up to play with, so this has all been built up starting from old desktop machines and expanded over time.