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There will also be references to the old hostname in /etc/postfix/generic and /etc/postfix/main.cf. I don't know yet if we simply need to edit those files or do something else.:
postconf -e myhostname=<hostname>
- postconf -e mydestination=<hostname>,localhost.<domain>,localhost
Obvisouly replace <hostname> and <domain> by the appropriate values
Change the bind settings
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