mdns-repeater-mikrotik/run.sh

#!/bin/bash
# on error exit
set -e
# set vlan parent interface
INTERFACE=eth0
# assign vlan ids via commandline parameter 1
VLANS=$1
if [[ -z "$VLANS" ]];then
	echo -e "No VLAN-IDs assigned through environment variable with name 'VLANS'!\nExit container."
	exit 1
fi
# build interface list with parent interface and vlan ids
ALLVLANIF=$(echo -n $VLANS | sed -re "s/\b([0-9]+)/${INTERFACE}.\1/g")

# get MTU of parent interface
MTU=$(ip link show $INTERFACE | grep -Ei 'mtu \d+' | cut -d " " -f2)

# cleanup non used vlan interfaces
for VLAN in $(ls -1 /sys/class/net | grep -E "^${INTERFACE}\\." | grep -Ev "$(echo $ALLVLANIF | tr ' ' '|')") ;do
	echo "Deleting orphaned interface: $VLAN"
	ip link delete $VLAN
done

# for each vlan id
for VLAN in $VLANS; do
	VLANIF="${INTERFACE}.$VLAN"
    # create vlan interface
    [[ ! -d "/sys/class/net/${VLANIF}" ]] && {
        echo "Creating interface ${VLANIF}"
        ip link add link $INTERFACE name "$VLANIF" mtu $MTU type vlan id $VLAN
    }
    echo "Bring up $VLANIF interface"
    ip link set "$VLANIF" up

    # starting DHCP client on interface
    [[ -f "/var/run/udhcpc.${VLANIF}.pid" ]] && {
        kill "$(cat "/var/run/udhcpc.${VLANIF}.pid")" >/dev/null
        rm "/var/run/udhcpc.${VLANIF}.pid"
    }
    echo "Starting dhcp client on ${VLANIF}"
    udhcpc -b -i $VLANIF -x hostname:"$HOSTNAME" -p "/var/run/udhcpc.${VLANIF}.pid"
done

echo "Starting mDNS repeater process ... "
# run repeater on vlan interfaces
exec /bin/mdns-repeater -f $ALLVLANIF