RUT955, set as passthrough mode, Unifi Security Gateway 3P WAN2 interface MAC address bound. Backup connection works fine for a while but then goes into a loop where the client issues a DHCP request, doesn't think it received an ip address and re-requests it, repeat every 5 to 15 seconds or so.
Rebooting the RUT955 or just Restart connection or Re-register fixes the situation and a proper connection is formed. Unifi support pinned the problem on your side saying "USG only sends the DHCP to renew if he loses the IP. Or keeps sending the request when it does not have the IP."
Sample event log from the RUT955:
226151S |
2019-12-23 16:01:17 |
DHCP |
Leased 213.216.234.87 IP address for client B4:FB:E4:XX:XX:XX - Passthrough in LAN |
226150S |
2019-12-23 16:01:10 |
DHCP |
Leased 213.216.234.87 IP address for client B4:FB:E4:XX:XX:XX - Passthrough in LAN |
226149S |
2019-12-23 16:00:54 |
DHCP |
Leased 213.216.234.87 IP address for client B4:FB:E4:XX:XX:XX - Passthrough in LAN |
226148S |
2019-12-23 16:00:47 |
DHCP |
Leased 213.216.234.87 IP address for client B4:FB:E4:XX:XX:XX - Passthrough in LAN |
Mobile connection seems sane:
Data connection state |
Connected |
IMEI |
XXXXX |
IMSI |
XXXXX |
ICCID |
8935806XXXXXXXF |
Sim card state |
Ready |
Signal strength |
-57 dBm |
Cell ID |
XXXXXX |
RSRP |
-93 dBm |
RSRQ |
-15 dB |
SINR |
-0.5 dB |
Operator |
DNA |
Operator state |
Registered (home) |
Connection type |
4G (LTE) |
Connected band |
LTE BAND 3 |
Bytes received * |
38.0 MB (39809103 bytes) |
Bytes sent * |
18.2 MB (19106212 bytes) |