OpenWRT on nagg.eu

Debian QEMU/KVM bridged networking and VLAN

Sun, 25 Jul 2021 00:00:00 +0000

By default on every Linux distro after installing QEMU and libvirt two kinds of networking are available:

NAT: VM sits behind a NAT.
MACVTAP: without going into much details it acts more or less like a bridged network, except not really. One of the most annoying limitations is that host to guest communication and vice versa are not really working well. Other important things might be broken as well, like for example VRRP. This mode is good for quick and dirty testing but not really for a stable environment.

BRIDGED networking is also supported by libvirt but requires some manual work.
A possible networking schema could be the following:

OPENWRT first run configuration guide

Sat, 12 Dec 2020 00:00:00 +0000

OpenWRT is a free open source Linux based operating system aimed at networking hardware.
Every time the system is upgraded to a newer version using the so called Sysupgrade BIN image every package the user manually installed gets lost; this makes the upgrade process very tedious especially if one does not properly write down all the customization he has made.
I don’t use many custom packages but QoS, DNS-over-HTTPS, USB support and vnstat are must have.

APC UPS and HP server gen8 not restarting automatically when power goes back online after shutdown procedure is already starded but not completed

Mon, 25 Jun 2018 17:35:54 +0000

I have got my hands on an APC UPS and some HP gen8 server, installed apcupsd on CentOS 7, connected the USB cable and everything was working fine except for this very annoying issue I had: * power goes down (pull the UPS power cord).

after some minutes the UPS battery threshold is triggered and the server shutdown procedure is launched by apcupsd.
power goes back up (plug in the power cord) while the server is already shutting down but the shutdown sequence is not yet completed.

RESULT: the server will not power itself up even if the correct setting is selected in BIOS (last power state or always on).
If the power stays offline for enough time for the server to completely shutdown and for the UPS to also shutdown once the power goes back online the server starts up automatically like it is supposed to do.
The only workaround I could think of to solve the issue is running a cron job on the router, which is running OpenWRT, to trigger wake-on-LAN for the server.
I don’t really like this solution, it feels hackish but still I could not find a better way to make the damn server power on automatically all by himself.
As for OpenWRT and wake-on-LAN, first of all install etherwake from LuCI or opkg:

LEDE/OPENWRT first run configuration guide

Sat, 04 Nov 2017 13:33:49 +0000

LEDE, formerly OpenWRT, is a free open source Linux based operating system aimed at networking hardware.
Every time the system is upgraded to a newer version using the so called Sysupgrade BIN image every package the user manually installed gets lost; this makes the upgrade process very tedious especially if one does not properly write down all the customization he has made.
I don’t use many custom packages but QoS, USB support and vnstat are a must have.