We face similar issues, we had 1 * server per VLAN, where each * had the same IP address, we achieve this with NAT.

                             <----> Asterisk 1 
                             <----> Asterisk 2
SIP LB <---> NAT <----> Asterisk 3

Your NAT device needs to be SIP aware, in our case we use Cisco ASA appliance device/ I know there is a ASA virtual device now which runs in VMware. 

Hope it helps


On Sun, Mar 12, 2017 at 4:02 PM, Alex Balashov <abalashov@evaristesys.com> wrote:
On Sun, Mar 12, 2017 at 10:48:37PM +0100, przeqpiciel wrote:

> Thank you for your respond. Obviously, I could set a port range per
> instance of Asterisk but I though about something more dynamic. But when I
> think on it more deep there is no any other solution.

Trying to run concurrent instances of something like Asterisk on a
single host is very challenging for this, among other reasons.

I recommend containerisation of some sort, e.g. OpenVZ. Give it a very
lightweight "host" environment of its own, with distinct networking.
Then the full range of ports will be available to every instance.

--
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
Web: http://www.evaristesys.com/, http://www.csrpswitch.com/

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