Hub4 modem mode issues

[ploo]

I think there's something fundementally wrong with the Hub4 and its ability to go into modem mode.

Getting it to go successfully into modem mode is very hit and miss, depends on specific sequence of events, and even then those don't always work. I was wondering if everyone else has these issues consistently?

I've seen some posts on the forum with specific power on and connection sequences. Ive tried them all, sometimes they work. Sometimes they don't. Today the power to the modem was turned off, turned it back on and modem mode didn't work - had to 'quickly' login during a window when it was reachable to get it back into router mode; but then all the same challenges with modem mode.

Here's the challenge:

1) Hub4 is in router mode and is happy

2) Login and switch to modem mode

3) Start pings to 192.168.0.1 and 192.168.100.1

4) Hub4 starts to come back, responds to pings on both IPs, or just on the .100.1 IP (depending on the mood that it's in), lights are solid white - then stops responding to pings, then eventually goes dim white. All this time, my router is trying to get its IP address (the one the Hub4 gives out later after its boot sequence). Doesn't get anything.

At this point the Hub4 is not reachable at all. Removing cable, inserting cable, nothing. A power cycle goes back into the loop above - if I'm quick enough, during step 4, I can log back into the Hub4 and switch it back into router mode. If I'm not, I have to power cycle again.

A reset brings it all back to router mode, default login, and I can go through the process above. Previously, if I reset and followed the process laid out in this post it would work (1 time in 3) - but recently, not even that.

To be honest, I'm at a bit of a loss. I never had this problem with the Hub3 - it was very simple to switch it from router mode, to modem mode, and back again, etc - it would always work.

But the Hub4 seems overley sensitive to boot seqeunces and very hit and miss. Either I've got a faulty one or this is a problem that the Hub4 has. Looking at all the posts in this forum about modem mode issues on the Hub4, I'd suggest there's something amiss with the device.

[legacy1]

Its likely a conflict when the hub boots and give out a temp IP before you get the WAN IP and the time window when if you don't do a DHCP after the temp IP lease ends.

You could do some testing with a ACL switch to block source 192.168.100.0/24 with a rule above to allow source 192.168.100.1 TCP source port 80. This way when your router does a DHCP discover it never gets a temp IP.

[jpeg1]

How long did you wait between your steps 2) and 3)  ?

You need to let it reboot and settle before trying to log in.

[ploo]

Yes, it's definately related to the DHCP process. It seems to be a bit of pot luck as to when the Hub4 decides to give out a proper WAN IP address.

The hub4, more often than not, gives out the temp IP address which expires, and then doesn't give out the WAN DHCP address (or the temp LAN one anymore either).

The only way back is to go into the router, give it a static address in the 192.168.0.0/24 range (yes I know) and then connect to the Hub4 on 192.168.100.1. If you reboot it from the GUI, then switch the router back to DHCP, it sometimes works, my mostly it doesn't.

Quite frankly, the Hub4 modem mode is broken - if you can get it successfully into modem mode and never touch it again, then it will work (until you need to power off the Hub4 for any reason), then it's back to coutless reboots of kit to try and get the ordering right to get a WAN IP address.

Never had any of these issues with the Hub3. I'm going back to router mode until this gets sorted (if it ever does).

[Tudor]

My Hub4 goes back into router mode ok when power cycled. When the power is applied it gives out an address of 192.168.100.82 and a default gateway of 192.168.100.254. The interface is then dropped and the correct WAN address is assigned. All this is visible in the logs of my Unifi Dream Machine Pro. Perhaps your router is not handling the sequence correctly.