swich / watch wan interfaces on router to swich between them based on cron or usage

switch_interface_ssh.sh

#!/bin/bash

interface=$1

# Check if the interface is valid and set the other interface
if [[ $interface == "wan" ]]; then
    other_interface="wanb"
elif [[ $interface == "wanb" ]]; then
    other_interface="wan"
else
    echo "Invalid interface: $interface"
    echo "Please choose either 'wan' or 'wanb'"
    exit 1
fi

# SSH into the OpenWrt router and switch the interface
echo "Switching to $interface..."
ssh root@192.168.1.1 "ifup $interface && sleep 30 && ifdown $other_interface" &

watch_interface_router.sh

#!/bin/bash

# you must install bash + bc, opkg install bash bc
# and also install and setup vnstat
# https://openwrt.org/docs/guide-user/services/network_monitoring/vnstat
# usage in cron every 10 min:
# */10 * * * * /root/scripts/watch_interface.sh wan 2 wanb
# 2 means if ussage is greater than 3GiB
# remember to also swich back interface in cron, like 4 am:
# 0 4 * * * /bin/sh -c 'ifup wan && sleep 30 && ifdown wanb'

# Function to check network usage
check_usage() {
    local interface=$1
    local usage_limit=$2
    local other_interface=$3

    # Check if the interface is down
    if ! ifconfig $interface | grep -q 'UP'; then
        echo "Interface $interface is down. Exiting."
        exit 1
    fi

    # Get the current network usage for received and transmitted data
    local usage_data=$(vnstat -i $interface --json d | jq '.interfaces[0].traffic.days[0] | {rx: .rx, tx: .tx}')

    local usage_rx=$(echo $usage_data | jq '.rx')
    local usage_tx=$(echo $usage_data | jq '.tx')

    # Add up the received and transmitted data
    local total_usage=$(echo "$usage_rx + $usage_tx" | bc)

    # Convert usage to GB
    local usage_gb=$(echo "$total_usage / 1000 / 1000" | bc)

    echo "Current usage: $usage_gb GB"

    # Check if usage exceeds limit
    if (( usage_gb > usage_limit )); then
        # Switch interface
        ifup $other_interface && sleep 30 && ifdown $interface
        echo "Usage is above limit - switching interfaces to $other_interface"
        logger -p notice -t switchnet "switch network to $other_interface with usage of $total_usage"
    else
        echo "Usage is below limit"
    fi
}

if [ $# -ne 3 ]; then
    echo "Usage: $0 <interface> <usage_limit> <other_interface>"
    exit 1
fi

check_usage $1 $2 $3

watch_interface_ssh.sh

#!/bin/bash

# Function to check network usage
check_usage() {
    local interface=$1
    local usage_limit=$2
    local other_interface=$3

    # Check if the interface is down
    if ! ssh root@192.168.1.1 "ifconfig $interface | grep -q 'UP'"; then
        echo "Interface $interface is down. Exiting."
        exit 1
    fi


    # Get the current network usage
    local usage_data=$(ssh root@192.168.1.1 "vnstat -i $interface --json d | jq '.interfaces[0].traffic.days[0] | {rx: .rx, tx: .tx}'")

    local usage_rx=$(echo $usage_data | jq '.rx')
    local usage_tx=$(echo $usage_data | jq '.tx')

    # Add up the received and transmitted data
    local total_usage=$(echo "$usage_rx + $usage_tx" | bc)

    # Convert usage to GB
    local usage_gb=$(echo "$total_usage / 1000 / 1000" | bc)

    echo "Current usage: $usage_gb GB"

    # Check if usage exceeds limit
    if (( usage_gb > usage_limit )); then
        # Switch interface
        ssh root@192.168.1.1 "ifup $other_interface && sleep 30 && ifdown $interface"
	echo "Usage is above limit - switching interfaces to $other_interface"
    else
	echo "Usage is below limit"
    fi
}

# Call the function with the desired interface, usage limit, and other interface
# check if arguments are passed
# if not, print usage
if [ $# -ne 3 ]; then
    echo "Usage: $0 <interface> <usage_limit> <other_interface>"
    exit 1
fi

check_usage $1 $2 $3