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When NTP is marked as unmanaged service then sipXecs won't generate any configuration (/etc/ntp.conf) or issue any service start / stop commands. This is up to the admin, however some other system components (like phones) still need info about NTP configuration. That's why in addition to turning service in an unmanaged service, admin can also specify additional NTP servers phones or other components should default to.
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The phone configuration will be automatically filled in with corresponding data
DNS
Managed service
DNS managed service means that you leave sipXecs to configure (generating zone files, resolv.conf) and start / stop DNS when needed (e.g. when configuration changed and needs to be applied).
Unmanaged service
When DNS is marked as unmanaged service creating configuration files and stopping / starting service it's up to admin. Since some other system component still need info about DNS configuration admin can specify additional DNS servers.
The gateway configuration will be automatically filled in with specified servers
DHCP
Managed service
Unmanaged service
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