I have this great problem, after weeks investigating a solution searching on the routing and freepbx side, I found that on phisical host my problem doesn't happens, so maybe is related to proxmox networking.
I have a freepbx kvm with around 50 extensions and 4 sip trunks. connectivity is provided by the internet provider's router that gives me a mask of public ips. Next to this router is a mikrokitk enterprise router that through mangle roules gives the public ip of the first router to my freepbx kvm, so there is no double nat here, everything of this kvm is exposed to the public ip. This configuration is working very well and we receive around 80 incoming calls with no problem. Obviously this is a production environment and needs to be secured, so I need an internet backup for this kvm. So I have other 2 super fast vdsls and a really good 4g lte connectivity. Any of these connections doesn't provide a public ip so everything is behind NAT, and if we consider the mikrotik in this case we have a double nat. but this is not important cause I have already tried removing the mikrotik in the middle with no success. at this point if I give connectivity to the kvm through any of these backup connections I will receive random errors during the trunk regustration. some times simply I receive authentication errors, or cannot comunicate with the sip provider, some times works but after rebooting I will receive again random errors. with a phisical host same configuration and connectivity this doesn't happens.
freepbx is a centos 7 distro and attached you will find my configuration. I know that this sounds strange, I m a senior asterisk user and I know that double NAT is akways a problem but I always found a solution, but this is the first time with a virtualized instance. Hope someone can give me at least a point of view.
many thanks
I have a freepbx kvm with around 50 extensions and 4 sip trunks. connectivity is provided by the internet provider's router that gives me a mask of public ips. Next to this router is a mikrokitk enterprise router that through mangle roules gives the public ip of the first router to my freepbx kvm, so there is no double nat here, everything of this kvm is exposed to the public ip. This configuration is working very well and we receive around 80 incoming calls with no problem. Obviously this is a production environment and needs to be secured, so I need an internet backup for this kvm. So I have other 2 super fast vdsls and a really good 4g lte connectivity. Any of these connections doesn't provide a public ip so everything is behind NAT, and if we consider the mikrotik in this case we have a double nat. but this is not important cause I have already tried removing the mikrotik in the middle with no success. at this point if I give connectivity to the kvm through any of these backup connections I will receive random errors during the trunk regustration. some times simply I receive authentication errors, or cannot comunicate with the sip provider, some times works but after rebooting I will receive again random errors. with a phisical host same configuration and connectivity this doesn't happens.
freepbx is a centos 7 distro and attached you will find my configuration. I know that this sounds strange, I m a senior asterisk user and I know that double NAT is akways a problem but I always found a solution, but this is the first time with a virtualized instance. Hope someone can give me at least a point of view.
many thanks
. Connect all your backup Internet links(lan side), and use a script to check if mikrotik have Internet via primary ISP (netwatch with scrips for up and down).... Another hint on mikrotik/linux - use netmap is much better and flexible insted of double nat.