Hi, i installed OpenWRT 19.7.2 on my EdgeRouter-X properly.
My ISP works under DHCP leasing. My problem is related to WAN connection: If I turnoff my modem or unplug and plug again the ethernet to my ER-X, OpenWRT does not detect that nor down the interface, then does not negotiate a new IP.
To get internet working again I must restart the interface manually.
How can I handle this issue? Thanks!
Example: I turn off my modem and I see this:
.
Hello, what is the output of uci export network ?
Use ssh to connect to the device.
Please use the "Preformatted text </>" button for logs, scripts, configs and general console output.
Please edit your post accordingly. Thank you! 
Hi trendy, here is the output. Thank you.
# uci export network
package network
config interface 'loopback'
option ifname 'lo'
option proto 'static'
option ipaddr '127.0.0.1'
option netmask '255.0.0.0'
config globals 'globals'
option ula_prefix 'fd67:63e4:92f8::/48'
config interface 'lan'
option type 'bridge'
option ifname 'eth0.1'
option proto 'static'
option ipaddr '192.168.1.1'
option netmask '255.255.255.0'
option ip6assign '60'
config device 'lan_eth0_1_dev'
option name 'eth0.1'
option macaddr 'XXXX'
config interface 'wan'
option ifname 'eth0.2'
option proto 'dhcp'
config device 'wan_eth0_2_dev'
option name 'eth0.2'
option macaddr 'XXXX'
config interface 'wan6'
option ifname 'eth0.2'
option proto 'dhcpv6'
config switch
option name 'switch0'
option reset '1'
option enable_vlan '1'
config switch_vlan
option device 'switch0'
option vlan '1'
option ports '1 2 3 4 6t'
config switch_vlan
option device 'switch0'
option vlan '2'
option ports '0 6t'
Nothing out of the ordinary here.
When you plug out the cable, do you see in Network-Switch page in Luci that the cable was removed?
Or if you give swconfig dev switch0 show , port 0 should show as down.
Are there any logs that the interface went down?
ifstatus wan; logread | grep -i wan; echo ; echo ; echo ; logread | grep -i eth0.2
I have the same output with and without the cable attached to the WAN port 
# ifstatus wan; logread | grep -i wan; echo ; echo ; echo ; logread | grep -i eth0.2
{
"up": true,
"pending": false,
"available": true,
"autostart": true,
"dynamic": false,
"uptime": 21895,
"l3_device": "eth0.2",
"proto": "dhcp",
"device": "eth0.2",
"updated": [
"addresses",
"routes",
"data"
],
"metric": 0,
"dns_metric": 0,
"delegation": true,
"ipv4-address": [
{
"address": "X.X.X.91",
"mask": 23
}
],
"ipv6-address": [
],
"ipv6-prefix": [
],
"ipv6-prefix-assignment": [
],
"route": [
{
"target": "0.0.0.0",
"mask": 0,
"nexthop": "X.X.X.X",
"source": "X.X.X.91/32"
}
],
"dns-server": [
"X.X.X.X",
"X.X.X.X"
],
"dns-search": [
"my.isp.dns"
],
"neighbors": [
],
"inactive": {
"ipv4-address": [
],
"ipv6-address": [
],
"route": [
],
"dns-server": [
],
"dns-search": [
],
"neighbors": [
]
},
"data": {
"hostname": "OpenWrt",
"leasetime": 63307
}
}
Thu Feb 27 21:05:21 2020 daemon.notice netifd: Interface 'wan' is enabled
Thu Feb 27 21:05:21 2020 daemon.notice netifd: Interface 'wan6' is enabled
Thu Feb 27 21:05:21 2020 daemon.notice netifd: Interface 'wan' has link connectivity
Thu Feb 27 21:05:21 2020 daemon.notice netifd: Interface 'wan' is setting up now
Thu Feb 27 21:05:21 2020 daemon.notice netifd: Interface 'wan6' has link connectivity
Thu Feb 27 21:05:21 2020 daemon.notice netifd: Interface 'wan6' is setting up now
Thu Feb 27 21:05:21 2020 daemon.notice netifd: wan (1153): udhcpc: started, v1.30.1
Thu Feb 27 21:05:22 2020 daemon.notice netifd: wan (1153): udhcpc: sending discover
Thu Feb 27 21:05:22 2020 daemon.notice netifd: wan (1153): udhcpc: sending select for X.X.X.91
Thu Feb 27 21:05:22 2020 daemon.notice netifd: wan (1153): udhcpc: lease of X.X.X.91 obtained, lease time 63307
Thu Feb 27 21:05:22 2020 daemon.notice netifd: Interface 'wan' is now up
Thu Feb 27 21:05:22 2020 user.notice firewall: Reloading firewall due to ifup of wan (eth0.2)
Thu Feb 27 21:05:21 2020 daemon.notice netifd: VLAN 'eth0.2' link is up
Thu Feb 27 21:05:22 2020 user.notice firewall: Reloading firewall due to ifup of wan (eth0.2)
# date
Thu May 7 19:39:53 UTC 2020
I have the feeling that something similar has been discussed before, but I cannot find it.
I summon @mk24, @lantis1008, @slh as they were involved in some similar topic and they might have something to suggest.