This page documents the fast recovery process for restoring AT&T Fiber bypass on the UniFi Dream Machine SE after UniFi OS updates. Firmware updates often remove wpasupplicant and disable the wired authentication service, which breaks the bypass. The steps below reliably restore connectivity.
Your AT&T bypass uses:
eth8wpa_supplicant/persistent/dpkg/bullseye/packages/wpa_supplicant-wired@eth8.serviceRestoring bypass always requires these two actions:
wpasupplicant and its dependency (libpcsclite1).wpa_supplicant-wired@eth8 systemd unit.wpasupplicantSSH into the UDM:
ssh root@udm.grandmasterj.com
Reinstall both required .deb packages:
dpkg -i /persistent/dpkg/bullseye/packages/libpcsclite1_*.deb
dpkg -i /persistent/dpkg/bullseye/packages/wpasupplicant_*.deb
Verify install:
wpa_supplicant -v
Enable the service so it survives reboots:
systemctl enable wpa_supplicant-wired@eth8.service
Start it immediately:
systemctl start wpa_supplicant-wired@eth8.service
Check status:
systemctl status wpa_supplicant-wired@eth8.service
You should see: active (running).
Try to renew the DHCP lease if the client is available on the current UniFi OS build:
udhcpc -i eth8
Important note: on the April 2026 recovery after a UniFi OS update, udhcpc was not present on the UDM build. In that case, restoring wpasupplicant and starting wpa_supplicant-wired@eth8.service was still enough for eth8 to acquire a public DHCP lease automatically. So if udhcpc returns command not found, do not panic — move on to interface and connectivity verification.
Test external connectivity:
ping 1.1.1.1 -c 3
View interface details:
ip addr show eth8
Check default routes:
ip route
Confirm DNS works:
nslookup cloudflare.com
Verify WAN status in the UniFi UI — it should no longer show “Offline.”
Check logs for errors:
journalctl -u wpa_supplicant-wired@eth8.service --no-pager
Most common issues:
wpasupplicant (reinstall it)eth8 is still the WAN port)udhcpc missing on newer UniFi OS builds (verify whether the lease already came back automatically before troubleshooting further)Restoring the bypass always requires:
If AT&T bypass ever fails after an update, these steps should bring it back quickly.
The bypass now auto-restores on boot via a persistent systemd service. No manual steps needed after firmware updates.
/persistent/restore-att-bypass.sh (survives firmware updates)att-bypass-restore.service (runs on every boot)/etc/systemd/system/, the script re-installs itself automaticallyThe script:
wpasupplicant and libpcsclite1 are installed; reinstalls if missing/persistent/system/ if it was wipedwpa_supplicant-wired@eth8.serviceIf the bypass fails after a firmware update, it should come back online on the next reboot automatically. Check status with:
systemctl status att-bypass-restore.service
systemctl status wpa_supplicant-wired@eth8.service
Observed during live recovery after a UniFi OS update (before automation was added):
wpasupplicant had been removed by the updatelibpcsclite1 and wpasupplicant, then enabling/starting wpa_supplicant-wired@eth8.service, restored WANeth8 acquired a public lease automatically after the service came upudhcpc was not available on that build, so the lease-refresh command was unnecessary