Apuntes de root

I’m experiencing kernel panics in a headless Raspberry Pi with Fedora 29 Server and need a way to capture what is happening.

First I tried to enable kdump, but this doesn’t seem possible. If someone has done it, I’d like to hear.

What I’m using now, is enabling netconsole to log all the kernel messages over the network to a rsyslog server. This is the config in the Pi:

/etc/modules-load.d/netconsole.conf:

With this recipe I have installed a VM in Google Compute Engine with an all-in-one OpenStack setup for testing purposes.

To set the window title in tmux or screen to the hostname you are connecting by ssh, add this to your ~/.bashrc:

settitle() {
    printf "\033k$1\033\\"
}

ssh() {
    local sshargs=("$@")
    local do_settitle=1
    tty -s || local do_settitle=0
    if [ "${TERM:0:6}" != "screen" ]; then
        local do_settitle=0
    fi
    if [ $do_settitle -eq 1 ]; then
        if [ "$1" == "-l" ]; then
            shift 2
        fi
       settitle "$*"
    fi
    command ssh "${sshargs[@]}"
    if [ $do_settitle -eq 1 ]; then
        settitle "bash"
    fi
}

Everyday is harder to manage old hardware or access outdated intranet websites because the browser security is tighter with every release. Many appliances use unsigned Java applets or insecure ciphers and protocols.

My first solution to this problem was to have a Windows VM in my laptop with old versions of everything: Firefox, Java, Flash… but running the VM in my underpowered laptop was too slow and made the system sluggish.

Here I describe how to run an old Firefox instance with an old Java.

With this recipe we will create a wireless access point in our laptop to share our wired Internet connection. This is quite useful where you only have a wired Internet connection (e.g. my work place) for giving access to your phone.

This is done in Fedora 25 Workstation with NetworkManager.

I’ve successfully monitored a Salicru SPS SOHO+ UPS with NUT following these steps.

In this example I have two Fedora servers, a master where the UPS is connected by USB and a client which is also powered by this UPS but monitors its status by network. With the default configuration the clients will be powered down in an outage when the battery reaches critical levels.

To improve my system’s security, I’ve configured Steam to be run as a different Linux account. This guide is inspired in this thread.

Voy a describir cómo configurar un router neutro con la conexión a Internet FTTH de Orange en España. El router en cuestión tiene el sistema pfSense basado en FreeBSD.

Hoy me ha llegado el aviso de que me iba a caducar el certificado de la FNMT, y en el proceso de renovación me obligaban a autenticarme con el DNIe, por lo que he tenido que repasar todo este tema.

La última vez que lo usé, tuve que compilar a mano los módulos de OpenDNIe y hacer unos cuantos malabares. Por fortuna, parece que la integración del proyecto con opensc ha dado sus frutos y no he tenido que usar ningún tipo de magia negra esta vez.

This little tip enables wake-on-lan on our network interfaces so the computer can be awaken with a magic packet from other host in the same network.