I am using mikrotik hex poe on 6.45.6.
WAN connects to Telstra NBN. It used to work perfectly on Telstra Cable. But seems like Telstra NBN using a different way doing DHCP server.
Mikrotik DHCP client get dhcp release for 1 hour. In the middle of that hour if not get ACK, after dhcp lease timeout, the Internet will drop. See below log.
16:14:30 interface,info sfp1-wan link down
16:14:30 dhcp,info dhcp-client on sfp1-wan lost IP address xx.xx.xxx.xx - lease stopped locally
16:14:38 interface,info sfp1-wan link up (speed 1G, full duplex)
16:14:40 interface,info sfp1-wan link down
16:14:46 interface,info sfp1-wan link up (speed 1G, full duplex)
16:15:35 dhcp,info dhcp-client on sfp1-wan got IP address xxx.xxx.xx.xx
It takes a while to detect that WAN lost the IP and cycle the interface to force a DHCP rebind. The whole process will get home internet down around 5-10 minutes. But it will happen every hour. Sometimes, no drop out the full day. But sometimes, happens every hour.
To isolate the problem, I also took out Telstra provided NBN compatible smart modem to get the DHCP IP address. And mikrotik router sit behind it. Surprisedly, The Telstra Modem DHCP renew works without any issue. It got 1 hour DHCP lease at the beginning, then after 35 mins, it will extend its DHCP lease to 1 day. So I don't understand why Mikrotik DHCP cannot act the same way.
I searched a lot threads who using Cisco device had similar issue with NBN DHCP drop out, and ended with Cisco IOS upgrade.
Not sure is this something that Mikrotik can help to make DHCP client compatible with NBN DHCP server? Or at least provide some customised option to make it work. Happy to provide supout.rif if anyone can help troubleshoot the issue. Thanks in advance.