USG Flex 100AX - port lan is down

mlik

Hello,

I have a problem with the Zyxel USG Flex 100AX hardware firewall. The logs show "Port 3 is down!" once an hour, then after 10 seconds "Port 3 is up!". I have a Ubiqiti U6-LR access point connected to port 3. Both devices are new. The hardware firewall has been updated to the latest versions - V5.38(ACFN.0), Ubiqiti has also been updated to the latest version. All ports P2-P5 are set to LAN1. In the firewall logs, apart from the system alert, there is often a Security Policy Control Match default rule, DROP [count=8] 255.255.255.255:67 ACCESS BLOCK. Both devices are connected to the same power strip.

I read old posts on the forum and with this type of problem, it turned out to be a software error.

Zyxel_Melen

Hi @mlik,

The log "Port 3 is down/up!" means the link up/down event. Since this is a layer 1 event, could you share your access point logs if the access point also link down/up? And have you changed the cable/port to check if this issue happens again?

"Match default rule, DROP [count=8] 255.255.255.255:67 ACCESS BLOCK." This seems like the DHCP packets from a DHCP server have been dropped. It is more likely you have set a security policy or configuration to prevent illegal DHCP servers from offering illegal IP addresses. It is less related to the link up/down event.