Running the "ifup wwan" command automatically at boot?

root-r · October 5, 2019, 10:59pm

hi,

i have a d-link dwr-921 lte router running openwrt 18.06.4

the router frequently loses its internet connection, then i mostly have to reboot, connect the router to a computer via network cable and run the commands

# ssh root@192.168.1.1 and
# ifup wwan

manually to bring the router back online.

i am wondering if its possible to automate this, so the router automatically issues the "ifup wwan" command while booting or after booting (so i only have to reboot the router when it loses its internet connection, with no need to go to the command line in addition).

my knowledge about linux is limited, but i suppose this should be done by a boot script, right? unfortunately, i have no experience with writing scripts :-/

what do you think? what would be the best way to set up openwrt to run the "ifup wwan" command automatically at boot?

your help would be much appreciated.

thank you

trendy · October 5, 2019, 11:07pm

There is an option in the interface settings to bring it up on boot.
For anything else there is rc.local

root@koutsomoura:~# cat /etc/rc.local 
# Put your custom commands here that should be executed once
# the system init finished. By default this file does nothing.

exit 0

vgaetera · October 6, 2019, 3:44am

See also:

Is reboot really necessary?

eduperez · October 6, 2019, 7:55am

You should not need to reboot the device, and you should not need to bring the interface up manually. Post your config files here, perhaps there is something weird there.

root-r · October 6, 2019, 5:57pm

thank you. by "option in the interface settings" you mean the bottom section in system -> startup in luci, right?
so it should look like this?
exit 0 ifup wwan

root-r · October 6, 2019, 6:27pm

thank you. i somehow got used to the thought that i have to reboot it to make the commands work, but maybe it was not necessary.

today i tried it and they worked without a reboot. so it looks like i have gotten that wrong.

are you sure that it is not normal that i have to bring up the wwan interface manually? the documentation sounds like this is normal, unless i'm misunderstanding it:
https://openwrt.org/toh/d-link/d-link_dwr-921#g3g_modem

where do i find my config files?

eduperez · October 6, 2019, 8:33pm

Well, if "uci set network.wwan.auto='0'" means "do not bring up on boot", I would try with "uci set network.wwan.auto='1'" and see what happens...

trendy · October 7, 2019, 1:56pm

Nope, this is for services. The right place is Network->Interfaces->WWAN-> Advanced Settings-> Bring up on boot.

No, the line exit 0 must be at the end, so whatever you add there keep it above.

jeff · October 7, 2019, 2:56pm

Another thing to consider is that many wireless modems fail to notify upper layers that the connection to the provider is down, so that the OS doesn't "know" that it needs to initiate reconnection. One page that discusses this is http://www.embeddedpi.com/documentation/3g-4g-modems/raspberry-pi-sierra-wireless-mc7304-modem-qmi-interface-setup I don't think the scripts there are generally useful for OpenWrt as they require Perl (which is for all-in-one routers, huge), but perhaps worth seeing if the interface is actually marked as "DOWN" (using, for example, ip link) when you lose connectivity.

I haven't written a "router friendly" version of the script myself, but understanding the source of the problem can help determine a resolution better than the sledgehammer of "reboot".

root-r · October 7, 2019, 5:16pm

i'm encountering a problem when trying to do that. there is no "advanced settings" tab and it just reads:
there is no device assigned yet, please attach a network device in the "physical settings" tab

however, i have a working internet connection right now.

here are two screenshots (i have removed details like ip-addresses):

what does this mean? why does it show the wwan interface as not connected in the second image?

trendy · October 7, 2019, 7:27pm

Post here the output of

uci show network

in preformatted text </>

root-r · October 7, 2019, 8:57pm

i hope this is what you meant...X always means that i replaced a letter or a number, let me know if you need to know any of those

root@OpenWrt:~# uci show network
network.loopback=interface
network.loopback.ifname='lo'
network.loopback.proto='static'
network.loopback.ipaddr='XXX.X.X.X'
network.loopback.netmask='XXX.X.X.X'
network.globals=globals
network.globals.ula_prefix='XXXX:XXXX:XXXX::/XX'
network.lan=interface
network.lan.type='bridge'
network.lan.ifname='eth0.1'
network.lan.proto='static'
network.lan.ipaddr='192.168.1.1'
network.lan.netmask='XXX.XXX.XXX.X'
network.lan.ip6assign='60'
network.lan_dev=device
network.lan_dev.name='eth0.1'
network.lan_dev.macaddr='XX:XX:XX:XX:XX:XX'
network.wan=interface
network.wan.ifname='eth0.2'
network.wan.proto='dhcp'
network.wan_dev=device
network.wan_dev.name='eth0.2'
network.wan_dev.macaddr='XX:XX:XX:XX:XX:XX'
network.wan6=interface
network.wan6.ifname='eth0.2'
network.wan6.proto='dhcpv6'
network.@switch[0]=switch
network.@switch[0].name='switch0'
network.@switch[0].reset='1'
network.@switch[0].enable_vlan='1'
network.@switch_vlan[0]=switch_vlan
network.@switch_vlan[0].device='switch0'
network.@switch_vlan[0].vlan='1'
network.@switch_vlan[0].ports='0 1 2 3 6t'
network.@switch_vlan[1]=switch_vlan
network.@switch_vlan[1].device='switch0'
network.@switch_vlan[1].vlan='2'
network.@switch_vlan[1].ports='4 6t'
network.wwan=interface
network.wwan.proto='wwan'
network.wwan.apn='internet'
network.wwan.pincode='XXXX'
network.wwan.auto='0'

tmomas · October 7, 2019, 9:27pm

Please use "Preformatted text </>" for logs, scripts, configs and general console output.

Please edit your posting accordingly.

eduperez · October 7, 2019, 9:49pm

If you insist...

root-r · October 7, 2019, 11:58pm

it would have been my next step to change it to '1'...but right now (after noticing that wwan is shown as not connected though it apparently should be) i'm fearing that there may be a basic problem with my configuration of network interfaces.

i suppose as long as i'm not sure about that, i shouldn't make any changes.

what do you say to the screenshots and the terminal output i posted? is it normal that wwan interface is shown as not connected?

vgaetera · October 8, 2019, 5:51am

That would be my first step:
https://openwrt.org/docs/guide-user/network/network_configuration?s=auto#common_options

anon50098793 · October 8, 2019, 8:18am

Perhaps if you can monitor neigh state...;

#!/bin/bash

VERBOSE=1
WANIF="eth0.2"
LOOPDELAY=3 #ooo
BACKOFFUP=3 #ooo
BACKOFFSTALE=2 #ooo
STALEMAX="7"
STALECOUNT="0"
DOWNCOUNT="0"    #STATSONLY
CHECKCOUNT="0"   #STATSONLY
WANREPAIRCOUNT=0
WANREPAIRMAX=10
WANREPAIRSTATE=
WANSTATUS=


GWIP="`ip route | grep default | cut -d' ' -f3`"
if [ ! -z "$GWIP" ]; then  WANSTATUS="UP"; else WANSTATUS="DOWN"; fi

if ifconfig | grep -v "         " | grep -v '^$' |  awk '{print $1}' | grep -q "$WANIF"; then
	echo "WANIF: $WANIF [ok]"
else
	echo "WANIF: $WANIF [not-present]"
	exit 1
fi

getgwip() {
	GWIP="`ip route | grep default | cut -d' ' -f3`"
	if [ ! -z "$GWIP" ]; then  WANSTATUS="UP"; else WANSTATUS="DOWN"; fi

}


checkup() {
	CHECKCOUNT=$[$CHECKCOUNT + 1]
	echo -n "CHECKUP:"
        if ping -c 2 -w 3 "${GWIP}" &>/dev/null; then
		echo " [ok]"
		WANSTATUS="UP"
		return 0
	else
		echo " [down]"
		WANSTATUS="DOWN"
		return 1
	fi
}


connectiondown() {

	echo "CONNECTION IS DOWN: $DOWNCOUNT"
	sleep 3
	logger -t wan-mon "${WANIF} DOWN:`date +%Y%m%d-%H%M` ${DOWNCOUNT}"
	echo "####!!! HANDLE REALDOWN !!! ###"; sleep 3

	WANREPAIRCOUNT=$[$WANREPAIRCOUNT + 1]
	WANREPAIRSTATE="FIXING" #REPAIR FAILED WAIT 

}

connectionup() {
	logger -t wan-mon "${WANIF} UP:`date +%Y%m%d-%H%M` ${DOWNCOUNT}"
}


showstats() {
echo -n "${WANRESULT:-LEARNING}"
echo -n ":::"
echo -n "${WANSTATUS:-ERRORSTATUS}"
echo -n " GW: $GWIP"
echo -n " STALECOUNT: $STALECOUNT"
echo -n " CHECKCOUNT: $CHECKCOUNT"
echo -n " DOWNCOUNT: $DOWNCOUNT"
echo -n " WANREPAIRCOUNT: $WANREPAIRCOUNT"
echo -n " WANREPAIRSTATE: $WANREPAIRSTATE"
echo ""
}


while true; do

	if (("$WANREPAIRCOUNT" > "$WANREPAIRMAX")); then echo "ENDING SCRIPT ::: WANREPAIRCOUNT > WANREPAIRMAX" && exit 21; fi
	getgwip

	#Rif [ -z "$GWIP" ] || [ "$WANSTATUS" == "DOWN" ]; then
	if [ -z "$GWIP" ]; then
		echo "MAINLOOP: no-gw-ip CALL CONNECTIONDOWN"; sleep 2
		connectiondown
	else
		WANSTATE="`ip neigh show dev $WANIF | grep -w "$GWIP"`"
		case $WANSTATE in
		*"FAILED"*) WANRESULT="FAILED"; WANSTATUS="DOWN"; ;;
		*"STALE"*) WANRESULT="STALE"; STALECOUNT=$[$STALECOUNT + 1]; ;;
		*"REACHABLE"*) WANRESULT="REACHABLE"; STALECOUNT=0; sleep $BACKOFFUP; ;;
		*"DELAY"*) WANRESULT="DELAY"; ;;
		*) WANRESULT="UNKNOWN"; WANSTATUS="DOWN"; ;;
		esac

		showstats
		if (("$VERBOSE" > "0")); then 
			: #logger -t wan-mon-stat "`showstats`";
		fi

		if (("$STALECOUNT" > "$STALEMAX")); then
			if checkup; then
				STALECOUNT=0
			else
				DOWNCOUNT=$[$DOWNCOUNT + 1]
				connectiondown
			fi
		fi

		if [ "$WANSTATUS" == "DOWN" ]; then
			echo "STATE is DOWN at bottom loop"; sleep 2		
			if checkup; then
				STALECOUNT=0
			else
				DOWNCOUNT=$[$DOWNCOUNT + 1]
				connectiondown
			fi
		fi
		
		if (("$STALECOUNT" < "$STALEMAX")); then sleep $BACKOFFSTALE; fi
	fi

	sleep $LOOPDELAY
done
echo "BAILING"
exit 0

root-r · October 8, 2019, 4:25pm

so to change the value, is it correct to run the following commands?

uci set network.wwan.auto='1'
service network reload

or is there a better way? e.g. editing the /etc/config/network file?

i still don't know if it is normal that the wwan interface is shown as not connected (see the screenshots i posted), but maybe this will change when i set the value to '1'

vgaetera · October 8, 2019, 4:36pm

Save and verify the changes:

uci commit network
uci get network.wwan.auto

root-r · October 8, 2019, 5:26pm

okay, it works now. i don't have to run the ifup wwan command manually anymore. thank you and everybody else

in luci, i now have the option to click on "restart" in the wwan section. however:

protocol is still shown as "unmanaged"
when i click "edit", it is the same as in the first screenshot i posted ("there is no device assigned yet...", protocol is shown as "static address")
the wwan_4 section is like in the second screenshot i posted (protocol "virtual dynamic interface (dhcp client)" with no option to click on restart, stop, edit or delete)

is this supposed to be this way?