Since old Ubuntu LTS doesn’t update package anymore,
some patches need add by yourself,
like munin if_ error.
: plugins/node.d.linux/if_
# iwlist first) if [[ -r /sys/class/net/$INTERFACE/speed ]]; then SPEED=$(cat /sys/class/net/$INTERFACE/speed 2>/dev/null) - if [[ "$SPEED" -gt 0 ]]; then + if [ -n "$SPEED" -a "$SPEED" -gt "0" ]; then echo $SPEED return fi