Hi - you are on the correct path and identified why it is not working - modem IP conflict, just a few tweaks and you should be connected.
1. Disconnect second modem [F@ST5366TN-A] from first. Connect your PC with a LAN cable to 5366TN-A and open web browser, enter 192.168.0.1 - enter in user ID and password to access admin screens, go to Modem Settings, LAN IPv4, and change its IP address from 192.168.0.1 to 192.168.1.1, the range will also have to change to 192.168.1.2 - 192.168.1.254 and SAVE. Reboot the modem.
2. Connect first modem F@ST5366 Ultra LTE LAN port to the F@ST5366TN-A WAN port and you should have Internet access from the second modem. The first modem will assign a client IP address to the second modem - log into the first modem to see its assigned address and it can be set up as a fixed IP address within the first modem's LAN IPV4 page to always use that address for modem 2 - see just under modem 1's LAN default settings in the Add Reserved Address section enter name, MAC address (listed on modem label) and the IP address it currently has been assigned and APPLY to save.
the problem originates on the 1st Optus modem that would not let me control the data flow?
Yes that is where the main problem is. Because the 1st modem is an Optus modem its trying to handle the phone call, but you want the phone call to be handled by the 2nd modem.
Because your configuration is a strange one there are a few things that need to be done to try and get it to work, and your unfamiliarity with the router/basic networking make it difficult to explain. Well start of by referring to them as routers instead of modems.
All the routers setting changes you need to make should be doable from the Modem Settings-->LAN IPv4 section. The subsections are used as follows:
This is where you change the IP address of the router. The 1st router should have the default 192.168.0.1 and you should change the 2nd router to 192.168.0.2.
In addition to the routers IP, the WAN port will effectively get its own unique IP address. The WAN port of the 1st router will get its IP address from Optus, and the WAN port of the 2nd router will get its IP address from the 1st router.
This is where the devices in your network get their IP addresses.
In the 1st modem you should change the IPv4 Pool Start from 192.168.0.2 to 192.168.0.3. This is to ensure that no other device is given 192.168.0.2.
In the second modem you need to set Enable to OFF. This is ensure that the devices only get their IP addresses from the 1st router so that there are no IP address conflicts in your network
Add Reserved Address
Press this button.
This is where you give static IP addresses to devices other then the router.
When the WAN port of router 2 is plugged into a LAN port of router 1, it should become selectable. Select the appropriate device from the dropdown list, and then click the apply button at the bottom of the page.
The IP address that is given here for the WAN port is the one that will be used for port forwarding the VoIP.
Note that generally wifi for devices connected to router 2 will work fine when router 2 is connected to router 1 via LAN port, but VoIP will not work because VoIP data has to enter router 2 via the WAN port.
That should get the general network up and running in your two 5366 setup.
The VoIP in router 2 probably won't work yet (because we have not done any port forwarding), but the first step is to ensure that your network works and that internet works for your devices.
The instructions I've given keep everything withing the 192.168.0.x subnet. That was deliberate to ensure that router 1 will still be accessible from any device on the network. Adding another subnet to xc's setup I think will cause more problems/confusion.
Also "MAC address (listed on modem label)" should be for the LAN not the WAN, at least that's how mine is.
I am a babe in the woods!
But will try.
Thank you for helping and your patience!
I have managed to follow @Mkrtich 1st part but could not do 2nd part.
I redid @YetAnotherAcc but had trouble.
I rewrote instructions because I am not sure if I should follow in sequence or just do each
piece all in each modem.
It is complicated by the fact that I have to disconnect all and go to either the house for #2 modem or garage attic for #1 modem to do each part.
For me, it is best just so give simple instructions first in sequence then explanation after.
1st White router: Now is the white 5366 LTE with SIM card
2nd Black router: Now is the Black 5366 TN
Do all changes in each Modem Settings-->LAN IPv4 section
Connect directly into 1st modem
#1 modem IP address = 192.168.0.1
#1 modem Changed DHCP IPv4 Pool Start from 192.168.0.2 to 192.168.0
Tether PC to internet from my phone as internet (only internet availble in the house)
Connect #2 modem from LAN port to my PC internet plug
Press Reset with safety pin on back of #2 modem to get rid of other changes
In PC browser type in 192.168.0.1
Log in with Username and password on label of modem.
#2 modem - Go into Modem Settings-->LAN IPv4 section
#2 modem - Change IP address = 192.168.0.2
#2 modem - Enable to OFF
#2 modem - DHCP IPv4 Pool Start from = ???
#2 modem ????? ERROR I get an error here for IPv4 Pool Start "Invalid IP Address"
SO I changed #2 modem IPv4 Pool Start = 192.168.0.1 and IPv4 Pool End = 192.168.0.3
Error went away, but is that the correct change to do?
#2 modem - Click on button "Add Reserved Address"
In entry box for MAC address, I typed in 12 digit MAC from back of Black box #2 modem
In entry box for IPv4 Address = 192.168.0.2 got error so typed in 192.168.0.1 (no error)
Got message " The action you performed may cause devices to temporarily lose connectivity. If
you changed the IP address of the gateway, you will have to change the IP address in your
browser before accessing the configuration interface again."
I selected "Yes" button
Got message " You can wait few seconds and click in the link below, to access the new gateway
Got message "Changes applied"
Unplugged #2 modem from my PC.
Pluged #1 modem LAN to #2 Modem WAN.
disconnected my tether from phone
Tested WIFI from #2 modem = no wifi
plugged PC internet cable to LAN #2 modem = no internet
plugged PC internet Cable into LAN #2 modem = no internet
restarted #1 and #2 modem, #1 LAN to #2 LAN. #2 LAN to PC = INTERNET!!
Wow, that took me a long time.
My phone still does not work, but I think from what you said before you would need to give me a 2nd set of instructions?
No worries and understood - difficult to know what other requirements users have apart from connecting the two modems together and it's good that you mentioned the alternative Access Point configuration for modem 2 which provides a one network option. All configurations have their peculiarities.
Probably just a terminology thing - I have always regarded the unique MAC address on the modem label to be associated with its gateway function address irrespective of how it is connected to another modem, be it via its LAN port (one network with DHCP Off in modem 2) or the WAN port (two networks configuration depicted in my post) - the reserved address provides stability of connection in between power restarts. Cheers
Unfortunately I don't have time to go through a step by step, but maybe @Mkrtich does (@Mkrtich if you do can you make it more bullet-pointy rather than paragraph style to make it easier to read/check off).
With router 1 in the attic, do you intend to use the wifi from the router 1 at all and/or its LAN ports other than to connect to router 2? If not then all you need to do is plug the long LAN cable into the NBN box instead of router 1, and then move router 1 to the living room and not use router 2 at all.
I have always regarded the unique MAC address on the modem label to be associated with its gateway function address irrespective of how it is connected to another modem
I don't know if there is any standard/common practice that dictates which MAC address in on the label but I always remember it as being for the LAN side.
be it via its LAN port (one network with DHCP Off in modem 2) or the WAN port (two networks configuration depicted in my post)
Each interface that can operate simultaneously should have its own MAC address, so commonly you would have at least 4 MAC addresses as follows:
@YetAnotherAcc - you are absolutely correct - I need to look at those MAC addresses more carefully - the WAN MAC address is nearly identical to the modem except it ends in a different pair of digits on my unit and probably the cause why my step 2 suggestion did not work as planned. Thanks for the clarification.
Happy to create a list process using your suggestion. Will test out before posting.
My apologies to both of you regarding my WAN MAC address misconception and the error in my step 2 that it caused. The Optus WAN MAC address is shown in the Device Info/General screen along with its firmware and should be used instead of the one printed on the modem label.
I use my Optus 5355TN-A for occasional testing only, with its IP address set as 192.168.50.1 and associated range as a secondary network connected to a primary modem with 192.168.0.1. It is at firmware level SG4YIT000105. When the F@ST5366 was originally released, it was not possible to alter it's IP Address and associated range, however that later changed to allow alterations in firmware releases with ..85 and ..105 suffix versions.
I did a Factory Reset Optus F@ST5366TN-A at the beginning and throughout the process to regain connection when things didn't work out. After a few attempts to alter 192.168.0.1, like xc, I also got the same error messages. My impression is that the modem's software is preventing a change to the fourth octet from a 1 to a 2, if the third octet remains a 0 - looks like it is quarantined - maybe a VLAN. It appears to me that you can conditionally change the IP address and associated range to any other entry as long as the third octect is not a 0 or any other number possibly reserved for other use?
@YetAnotherAcc - Have you successfully been able to change the IP address from 192.168.0.1 to 192.168.0.2? I can't think what may be causing the issue or what I may have done wrong?
1. Optus Modem in default IP 192.168.0.1 and range 192.168.0.2 to 192.168.0.254
2. Primary modem start IP range edited to begin at 192.168.0.3.
2. Connect PC to Optus modem - allocates 192.168.0.2 to PC - so changing modem IP to same may present an issue but after DHCP turned off maybe not?
3. Editing the modem IP address to 192.168.0.2 and then Disabling DHCP brings up red Error 'Invalid IP Address' in the Start range. Edit Start range to 192.168.0.3 and Apply to save allows change to be accepted but can't access the Optus modem or the Internet from a PC after the Optus modem is connected with a WAN cable to the primary modem. Optus modem display panel shows Internet and WAN LEDs On. Rebooted modem and PC, same outcome.
I also used 192.168.0.3 for the Optus modem with Start range beginning with 192.168.0.4 - made no difference after modem and PC Restart.
I guess this important step needs to be clarified before we proceed to next steps. Some modems place restrictions on substitute IP Addressing - one of my other test modems does not allow you to use 192.168.2.1 as it is used by its Guest Networking function but 192.168.1.1 is OK.
@xc - I got the same result as you did following the "Yes" button section of your post - no Internet. I think the reason you finally got Internet is that you did a LAN-LAN connection at the end, avoiding the WAN port which may be why VoiP is not working. The 'Add Reserved Address' was intended for modem #1 (with corrected WAN MAC now), not modem #2.
You did well given the circumstances. Once we clarify the initial IP Address change step, we can try again afresh with a new process list.
I too have my test 5366 normally at 192.168.50.1 as its a spare.
I first changed it to 192.168.0.1 (didn't want to do a factory reset) to get it to a standard state. I then changed it to 192.168.0.2 and IP pool start to 192.168.0.3 no problem (at the same time). The only strange thing was that I had to press the apply button twice.
I did all my changes through my phone as the 5366 is not connected to my network at all. I did have to disable/enable my phone's wifi to get it to release its IP address. As its through wifi I suspect the the IP lease was released immediately upon wifi disconnection. But as you are connecting via LAN i'm assuming the IP lease is not getting released automatically.
Normally when I tell people to give their devices a static IP address for things like their games consoles or VoIP devices I tell them to just pick a high IP number like 192.168.0.222 which would have a very very low chance of already being assigned by DHCP to another device. My initial thought was to do something similar. I should have gone with my gut and just suggested to use 192.168.0.254 for router #2, and you wouldn't even have to bother with having to change the pool range.
Thanks again for trying to help.
After the IP changes, my internet connection was intermittent then later went off.
I called Optus help desk.
They told me that my modem is automatically configured and was trying to reconnect, but could not with the IP changes and then shut down.
So I have no choice but the cabling option for the phone line as I need signal for the 2 WIFI in the very distance locations that each are at.