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Have a “host” machine with a recent version of Docker Engine and Docker Compose installed.
The “host” machine must have the network properly configured according to the network architecture.
In case of a Master node configured with a SIP Registrar, at least two IPs are required.
The “host” machine should not execute other services which may clash with the ports used in your services.
Exception: The Master node should have an MTA installed, such as “postfix” to send voicemail emails from mailboxes.
When a “SMTP relay" server is being usedrequired, it must be configured as detailed in this Configuring email relay for voicemails .
The “host” machine must not limit the connection to your services through a firewall.
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