Weird Problem (WAN disconnect every saturday or sunday)

Installing and Using OpenWrt
1

I have this weird problem where I lost internet connection every weekends (saturday or sunday at specific time), only after I restarted the WAN interface or router then the problem goes away... until next week.

My current configuration is intel nuc with USB EA300 gigabit (RTL8153) to wan port) virtualized in proxmox and OpenWRT 19.07.4 stable, WAN is connected to ISP GPON fiber optic modem (ZTE) and using bridged configuration to bypass NAT. Previously I had similar problem with snapshot on Raspberry Pi 4 and same USB Gigabit ethernet. At first I thought it's unstable USB Gigabit ethernet but this is the 3rd adapter that I've tried and all shows similar problem.

Then I've tried switching to OpnSense (in proxmox, same hardware configuration), there was almost no weird log during internet loss except that during the disconnect I noticed that in WAN connection (in OpnSense log) :

dhclient[53240] bound to 10.88.138.210 -- renewal in 1800 seconds.
changed to this after restarting interface
dhclient[66388] bound to 10.88.142.56 -- renewal in 1800 seconds.

It seems that my ISP issues DHCP refresh every 30 minutes or so, and every week on saturday or sunday it changes the subnet segment which both OpenWRT and OpnSense failed to receive new IP's, I haven't tried using non USB ethernet for WAN Port though.

Is there a script to detect subnet change in WAN and initiate interface restart?

2

I have similar experiences with my Zyxel LTE routers operating in bridge mode. For me the problems seem to be the bridge mode in conjunction with DHCP.

When a DHCP client (e.g. your openwrt router) ask for an IP the first time, it sends a DISCOVER message. After it got the IP, it regularly renews the lease depending on the lease time.

When the RENEW isn't answered or not acknowledged (because the old IP isn't valid anymore), then the client repeats several times a renewal. Depending on the lease time this can take more than one hour. During this time the client has no internet access.

If these renewals do not suceed, then the client sends a DISCOVER message. If you have a connection to your ISP, this DISCOVER normally suceeds and the client has internet access again.

You can enforce a DISCOVER with the ifup wan command on the router.

So the task/solution is to quickly detect the loss of internet access and then initiate an ifup wan. Of course, this can be done by a permanently running background job.

I think, you cannot completely eliminate the loss of internet access, but only minimize the down time.

Another approach would be to setup a time scheduled ifup wan at a time, which is convienent for you (e.g. when nobody needs internet access). So you interrupt the connection before your ISP does it.

1 Like
3

Thanks, I'll try to check on ifup wan command first.

the problem is to detect loss of internet access, most of the scripts I saw depends on initiate ping to several host every minutes which I didn't quite like it, maybe force DISCOVER only after first RENEW function didn't answered / acknowledged?

as for scheduling ifup wan. I've tried both restarting wan interface or reboot the system during weekdays (internet running normally) and still get the same WAN IP address. It seems only if it's iniatiated from ISP side then the wan ip address will change.

4

You can ping just the ISP gateway.

The DHCP client doesn't seem to supports this.

5

I think I found the culprit after similar problem occured using opnsense I tried to remove WAN ipv6 (my provider doesn't have anyway), after about 2 weeks I see that the ipv4 wan get new ip address everytime it's assigned and no internet disconnection occured until now, hopefully it's resolved but I still try to monitor it for another weeks.

6

Disregard my previous post, the problem still exists. Here's the log after the internet (wan) become idle and I have to restart wan interface :

Mon Dec  7 16:22:06 2020 user.info : info: guest-ping called
Mon Dec  7 16:22:20 2020 daemon.notice netifd: wan (1832): udhcpc: sending renew to 10.89.192.1
Mon Dec  7 16:22:35 2020 daemon.notice netifd: wan (1832): udhcpc: received SIGTERM
Mon Dec  7 16:22:35 2020 daemon.notice netifd: Interface 'wan' is now down
Mon Dec  7 16:22:35 2020 daemon.notice netifd: Interface 'wan' is disabled
Mon Dec  7 16:22:35 2020 daemon.notice netifd: Interface 'wan' is enabled
Mon Dec  7 16:22:35 2020 daemon.notice netifd: Interface 'wan' is setting up now
Mon Dec  7 16:22:35 2020 kern.info kernel: [388838.821307] 8021q: adding VLAN 0 to HW filter on device eth1
Mon Dec  7 16:22:35 2020 daemon.notice netifd: wan (19604): udhcpc: started, v1.30.1
Mon Dec  7 16:22:35 2020 daemon.notice netifd: wan (19604): udhcpc: sending discover
Mon Dec  7 16:22:38 2020 daemon.notice netifd: wan (19604): udhcpc: sending discover
Mon Dec  7 16:22:38 2020 daemon.notice netifd: wan (19604): udhcpc: sending select for 10.88.140.189
Mon Dec  7 16:22:38 2020 daemon.notice netifd: wan (19604): udhcpc: lease of 10.85.143.126 obtained, lease time 3600
Mon Dec  7 16:22:39 2020 daemon.notice netifd: Interface 'wan' is now up
Mon Dec  7 16:22:39 2020 user.notice SQM: Stopping SQM on eth1
Mon Dec  7 16:22:39 2020 user.notice SQM: Starting SQM script: layer_cake.qos on eth1, in: 30000 Kbps, out: 30000 Kbps
Mon Dec  7 16:22:39 2020 user.notice SQM: Using generic sqm_start_default function.
Mon Dec  7 16:22:39 2020 user.notice SQM: layer_cake.qos was started on eth1 successfully
Mon Dec  7 16:22:39 2020 user.notice firewall: Reloading firewall due to ifup of wan (eth1)

before this my (private) wan address have different subnet (eg. 10.85.112.96 , last 2 block)

7

Did you try hotplug?
https://openwrt.org/docs/guide-user/base-system/hotplug

8

I've just read about hotplug and it seems the event triggered when interfaces down?
Which in this case the interface still up but since the ISP gateway provide new ip address with different subnet nothing ever happened in the log even though the internet is disconnected.

Or perhaps pingcheck is better option? I see OpenWrt has this modules and I try to read about it first although I'm not too comfortable of having to constantly ping every x seconds just to check connectivity.

9

Doesn't it trigger an ifupdate event?

1 Like
10 
cat <<'IOU' > /etc/odhcp6c.user
#!/bin/sh

filterset() {
	while read THING; do
		case $THING in
			"PS"*|"LINENO"*|"HOSTNAME"*) continue; ;;
			"USER"*|"TERM"*|"SHLVL"*|"PPID"*|"PATH"*|"OPTIND"*|"IFS="*|"N="*|"'"|"PWD="*|"HOME="*|"_C"*) continue; ;;
			*"_J"*|"J_"*|"LOGNAME="*|"hlogfile"*|"_C"*) continue; ;;
			*) echo $THING; ;;
		esac
	done
}

DHCPDEBUG=1
if [ ! -z "$DHCPDEBUG" ]; then
	if [ ! -z "$PROTO_IP6ADDR" ]; then OOOn="odhcpc6.user"; else OOOn="udhcpc.user"; fi
	OOO="/etc/$OOOn"
	LOGOUT="/tmp/$OOOn.log"
	logger -t "$OOO" "${0} $LOGOUT ${*}" 

	case "$OOOn" in
	odhcpc6.user)
		logger -t "$OOO" "${ADDRESSES} ${PROTO_PREFIX6}" 
		logger -t "$OOO" "INTERFACE: ${INTERFACE} interface: ${interface}" 
		logger -t "$OOO" "RA_MTU:$RA_MTU SERVER:$SERVER"
	;;
	udhcpc.user)
		logger -t "$OOO" "${0} $ip/$mask/$BROADCAST lease:$lease"
		logger -t "$OOO" "INTERFACE: ${INTERFACE} interface: ${interface}"  
	;;
	esac

	set | filterset >> ${LOGOUT}
fi
IOU
1 Like
11

I suppose but looking at the wan ip address at that time it's still using the old ones (nothing on system log), only after restarting wan interfaces then it changed the wan ip address to new one.
Still I try to look into it, is this command right?

#!/bin/sh
if [ "${ACTION}" == "ifupdate" ] && [ "${DEVICE}" = "eth1" ]
then
    ifdown wan
    sleep 2
    ifup wan
fi
12

What does this commmand do? I run the script and it adds odhcp6c.user in the etc folder, is there anything that I have to run after that?

13 
ln -s /etc/odhcp6c.user /etc/udhcpc.user
logread
14 
Fri Dec 11 22:05:04 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Fri Dec 11 22:05:04 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Fri Dec 11 22:05:04 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Fri Dec 11 22:05:04 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Fri Dec 11 22:05:04 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Fri Dec 11 22:35:04 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Fri Dec 11 22:35:04 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Fri Dec 11 22:35:04 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Fri Dec 11 22:35:04 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Fri Dec 11 22:35:04 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Fri Dec 11 23:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Fri Dec 11 23:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Fri Dec 11 23:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Fri Dec 11 23:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Fri Dec 11 23:05:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Fri Dec 11 23:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Fri Dec 11 23:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Fri Dec 11 23:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Fri Dec 11 23:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Fri Dec 11 23:35:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 00:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 00:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 00:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 00:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 00:05:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 00:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 00:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 00:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 00:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 00:35:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 01:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 01:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 01:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 01:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 01:05:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 01:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 01:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 01:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 01:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 01:35:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 02:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 02:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 02:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 02:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 02:05:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 02:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 02:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 02:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 02:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 02:35:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 03:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 03:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 03:05:06 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 03:05:06 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 03:05:06 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 03:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 03:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 03:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 03:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 03:35:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 04:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 04:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 04:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 04:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 04:05:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 04:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 04:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 04:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 04:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 04:35:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 05:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 05:05:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 05:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 05:05:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 05:05:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Sat Dec 12 05:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: sending renew to 10.88.128.1
Sat Dec 12 05:35:05 2020 daemon.notice netifd: wan (26959): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Sat Dec 12 05:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Sat Dec 12 05:35:05 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Sat Dec 12 05:35:05 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1

this is recent log from logread (I've cut only last too last few lines because all are similar only different in times), currently the internet is still working for few days (usually after 7 days it begin receiving new ip address)

15

Here's a workaround for your problem, but it may require some tuning:

cat << "EOF" > /etc/udhcpc.user
logger -t udhcpc "${1} ${ip}/${mask}"
ipaddr_dhcp="$(uci get network.wan.ipaddr_dhcp)"
if [ "${1}" = "bound" -o "${1}" = "renew" ] \
&& [ "${ip}/${mask}" != "${ipaddr_dhcp}" ]
then
sleep 2
killall -SIGUSR1 udhcpc
uci set network.wan.ipaddr_dhcp="${ip}/${mask}"
fi
EOF

https://openwrt.org/docs/guide-user/network/protocol.dhcp#dhcp_client_scripts

1 Like
16

thanks, will try. What tuning do I have to set for my setup? I already set sleep to 30s just because it's a bit too often.

17

I can only guess as I cannot reproduce your issue.
Checking the log should be a good starting point:

logread -e udhcpc
18

thanks, will wait for few days for any change (I've just upgrade to 19.07.5)

Sun Dec 13 15:34:36 2020 user.info : info: guest-ping called
Sun Dec 13 15:34:47 2020 user.info : info: guest-ping called

I also noticed system logs getting full with this message since enabling the check, is this related?

edit : now the log doesn't appear again, odhcp and dnsmasq services are disabled though (I use pi-hole in another vm as dhcp and dns server).

19

This message should be related to virtualization:
https://github.com/qemu/qemu/blob/master/qga/commands.c#L62

20 
Wed Dec 23 22:52:19 2020 daemon.notice netifd: wan (1843): udhcpc: sending renew to 10.88.128.1
Wed Dec 23 22:52:19 2020 daemon.notice netifd: wan (1843): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Wed Dec 23 22:52:19 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Wed Dec 23 22:52:19 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Wed Dec 23 22:52:19 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Wed Dec 23 22:52:19 2020 user.notice udhcpc: renew 10.88.131.10/19
Wed Dec 23 23:22:19 2020 daemon.notice netifd: wan (1843): udhcpc: sending renew to 10.88.128.1
Wed Dec 23 23:22:19 2020 daemon.notice netifd: wan (1843): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Wed Dec 23 23:22:19 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Wed Dec 23 23:22:19 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Wed Dec 23 23:22:19 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Wed Dec 23 23:22:19 2020 user.notice udhcpc: renew 10.88.131.10/19
Wed Dec 23 23:52:19 2020 daemon.notice netifd: wan (1843): udhcpc: sending renew to 10.88.128.1
Wed Dec 23 23:52:19 2020 daemon.notice netifd: wan (1843): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Wed Dec 23 23:52:19 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Wed Dec 23 23:52:19 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Wed Dec 23 23:52:19 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Wed Dec 23 23:52:19 2020 user.notice udhcpc: renew 10.88.131.10/19
Thu Dec 24 00:22:20 2020 daemon.notice netifd: wan (1843): udhcpc: sending renew to 10.88.128.1
Thu Dec 24 00:22:20 2020 daemon.notice netifd: wan (1843): udhcpc: lease of 10.88.131.10 obtained, lease time 3600
Thu Dec 24 00:22:20 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script /tmp/udhcpc.user.log renew
Thu Dec 24 00:22:20 2020 user.notice /etc/udhcpc.user: /lib/netifd/dhcp.script 10.88.131.10/19/10.88.159.255 lease:3600
Thu Dec 24 00:22:20 2020 user.notice /etc/udhcpc.user: INTERFACE: wan interface: eth1
Thu Dec 24 00:22:20 2020 user.notice udhcpc: renew 10.88.131.10/19
Thu Dec 24 00:52:20 2020 daemon.notice netifd: wan (1843): udhcpc: sending renew to 10.88.128.1
Thu Dec 24 01:07:20 2020 daemon.notice netifd: wan (1843): udhcpc: sending renew to 10.88.128.1

The "error" occured again after a weeks and a half, wan and internet connection suddenly off at "Thu Dec 24 00:22:20 2020". How do I check if udhcpc.user runs?