Tag Archives: ipxe

Too good to #0012

Today: Mounting tar archives, a novel take on uptime, ipxe escapes.

ratarmountAccess large archives as a filesystem efficiently, e.g., TAR, RAR, ZIP, GZ, BZ2, XZ, ZSTD archives

$ virtualenv ~/.local/ratarmount
$ ~/.local/ratarmount/bin/pip3 install -U ratarmount
$ ~/.local/ratarmount/bin/ratarmount
$ install -D ~/.local/ratarmount/bin/ratarmount ~/bin/

$ mkdir -p ~/mnt
$ curl -O https://data.iana.org/time-zones/tzdata-latest.tar.gz
$ ratarmount tzdata-latest.tar.gz ~/mnt
$ find ~/mnt
$ fusermount -u ~/mnt

tuptimeReport historical and statistical real time of the system, keeping it between restarts. Total uptime

tuptime calculates overall uptime of the system it’s running on. It also flags shutdowns as “BAD” if it comes up without having been gracefully stopped before.

As I grew up in an age where uptime braggery was common even among professionals, my entirely unreasonable use case here is to determine uptime since the previous unclean shutdown:

function tuptime-graceful () {
        local tuptime_since=1
        local temp_array
        while read -r line 
                if [[ "${line}" =~ ' BAD ' ]]
                        read -r -a temp_array <<< "${line}"
                        tuptime_since=$(( temp_array[0] + 1 ))
        done < <(tuptime --table --order e --reverse)
        tuptime --since "${tuptime_since}"

Ampersand in ipxe script

Example is from a Debian preseed environment where preseed/late_command downloads and executes a shell script

set amp &
set latecmd in-target wget ${script_url} ${amp}${amp} in-target bash script.sh
kernel [...] preseed/late_command="${latecmd}"