I want to update every accounts dns file with my hostmaster email, instead of going through each dns file manually how can I update all at once?

Use the replace command;

Backup all your dns records first



Execute;



I haven't tested it but it should work. You may want to test it on a few files first to make sure it works as expected.

Won't work, because you have to increment the serial number before the changes will take.

The only way I know of is to use one of the GUI tools for something like that... or perhaps Webmin will allow you to mass-edit the SOA.