Quoth Randy Bush:
@ IN SOA ns.isp.net. netmaster.isp.net. ( 1998100100 86400 3600 604800 345600 ) s/netmaster/hostmaster/ see RFC 2142
or, i think it was piet who recommended being conservative, and do not relying on aliases, rather use a real mailbox name.
So that person can safely go on a two-week holiday? I'd rather put in a real hostname and not rely on MX records, including possible breakage. If you're real paranoid, register your domain also as a host with InterNIC (sort of 'ibm.com'), make its address the address of your primary mail exchanger; even if InterNIC has a minor screw-up - like "forgetting" your NS records - there's a chance your A record survives. This happened some time ago, unfortunately (for IBM, who were one of the domains lost this way) the host known at InterNIC as 'ibm.com' didn't run any SMTP daemon. (Remember that sendmail falls back to A records if it can't find any MX records for a host.) Good comments for the rest, I agree wholeheartedly with all of them, also with those from other people. Take care, -- Niels Bakker, * * EuroNet Internet BV Network Operations * * Herengracht 208-214 * 1016 BS Amsterdam NJB9 * +31 (0)20 535 5555