Liman quoting "Martin J. Laubach" <mjl@emsi.priv.at>:

| company.xy. MX 0 mailserver.company.xy.

Perhaps the note should mention that a CNAME is not allowed here?

CNAME RRs are not mentioned in the document, so to make this advice understandable an explanation would have to be added. There are other mistakes like using IP addresses in the MX target field or pointing to random mailservers (which noone notices until a problem occurs an then in most cases mail is lost due to relaying restrictions). For the sake of brevity I'd advocate for keeping this as is and put a list of popular errors (and how to avoid them) in the "long" document.

| ; The following is the list of computers at your site. To the left | ; should go the hostnames of the hosts.

And perhaps here mention that underscores in host names are not permitted?

Same here. To cover this completely, the allowed character set for hostnames (modulo veto from down under :-) must be shown, which again would extend the length of the document more than necessary. There's one minor nit. In the SOA dosument the daily versioning starts at "01" whereas the "configuration example" starts at "00". I think the "01" was the result of some discussion, but I do not have a strong preference for either of both. However, the two documents should be consistent. -Peter