3CX SBC in HA mode - issue

[timbo343]

I've done test after test after test with setting up 3BX SBC in HA mode but can I heck get a HyperV VM Linux talk to a physical Linux when the SBC boots to HA mode but yet both machines can ping each other, ping the outside world, provision as a SBC.

 

The issue is the physical box which says during HA provision:

"Error: could not connect to controller: Connection refused"

 

100.3 is the Linux VM

100.4 is the physical PC

[Davit2005]

Could this be down to promiscous mode on VM/Network???

[timbo343]

Just now, Davit2005 said:

Could this be down to promiscous mode on VM/Network???

Would that be on the HyperV VM or the physical box running the SBC locally?

[Davit2005]

I would look at the VMs network setting, unlikely to be the physical box.

 

If multiple MAC addresses are on the same virtual NIC or potentially for failover reasons it could cause an issue.

Edited May 13, 2025 by Davit2005

[timbo343]

Ah, ok. So I thought it might be the attached, it's made no difference.

[timbo343]

So i've flipped the 2 machines around, now the first HA SBC is on the physical PC and works as expected, however the VM being the secondary SBC in the HA doesn't work.

[timbo343]

Total loss with this now.

- 2 physical machines on the same VLAN that can ping each other and ping external IP addresses and Domains.

- In the Smoothwall the rule is set to allow everything out in the Firewall and Guardian.

- I've set Source NAT & LLB rules for the VLAN to go down one particular line

 

Yet still the second SBC will not work

[Davit2005]

Try that setting for allow MAC address spoofing. TBH I've not done much on Hyper-V at all, always gone bac to ESX after getting frustrated, lol.

 

But if the 3cx uses vrrp it could be a cause??

 

Another thought would be try the 3cx user forum

Edited May 13, 2025 by Davit2005

[timbo343]

5 minutes ago, Davit2005 said:

Try that setting for allow MAC address spoofing. TBH I've not done much on Hyper-V at all, always gone bac to ESX after getting frustrated, lol.

 

But if the 3cx uses vrrp it could be a cause??

I had that ticked before and it didn't work. Part of me thinks it is the Smoothwall at fault.

[timbo343]

Think i'm going to take both physical machines home to see what it does on a connection away from a Smoothwall.

 

I am still getting connection refused with 2 physical PCs though.

[timbo343]

I feel absolutely defeated by this!

 

When I have got 2 Linux VMs running on the same laptop the HA works without any issues, they both fail over to each other.

 

When i start introducing physical machines into the mix or have 2 physical machines acting as HA devices, they do not fail over to each other and i'm starting to wonder why?!

 

I really do not know what i'm doing wrong.

[timbo343]

Ok, i think i know why it's not working. The instructions for HA say

 

"Having the same network interface(s). For example ens192 on both machines"

 

I've got 3 machines (2 physical and 1 Virtual). Each have different interfaces. One has eno2, another has eth1 and the third has enp1s0.

[timbo343]

Finally got it working with a bit of help from method 1 in this article - https://syslinuxos.com/renaming-network-interfaces-on-linux-to-eth0/

 

Both devices need to have the same interface name for the SBC HA to fail over from the first SBC to the second. If this isn't the case, then once the SBC is up and you are at the login prompt, log in to the system as root.

 

Run sudo nano /etc/default/grub

 

add GRUB_CMDLINE_LINUX=”net.ifnames=0 biosdevname=0″ to underneath GRUB_CMDLINE_LINUX_DEFAULT=”quiet”

Save the config (ctrl+S) then exit out the editor (ctrl+X)

 

Run sudo grub-mkconfig -o /boot/grub/grub.cfg

Run sudo reboot to reboot the system.

 

Log back in to the system as root. 

 

Run sudo nano /etc/network/interfaces

Change the ethernet name to eth0

 

Save the config (ctrl+S) then exit out the editor (ctrl+X)

 

Run sudo systemctl restart networking.service

 

Run ifconfig to confirm the interface has changed to eth0.

 

Run sudo reboot to reboot the system.

 

Continue to run the SBC HA setup process.

[timbo343]

Confirming this works in production with a VM linux and a physical box.

[pete]

Mind posting to see if that change persists after the SBC is next patched?

 

(I know it should if they're following best practises and not amending edited config files without asking, but.....)

[timbo343]

13 minutes ago, pete said:

Mind posting to see if that change persists after the SBC is next patched?

 

(I know it should if they're following best practises and not amending edited config files without asking, but.....)

Aye, can post an update next time the SBC is patched - whenever that will be.

 

It doesn't take long to fire up 2 SBCs in HA mode.