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Note: SELinux has to be turned off for sipX, which means that the Fedora security policy for the named DNS server is turned off as well. You therefore should run named in a chroot jail, which we will do in a second step. Refer to man named.
You should not use the domain name __"example.com"_ - you should register a real domain name; there are many ISPs and DNS providers that can help you with setting this up._
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