On Mon, Aug 09, 2010 at 05:36:33PM +0100, Brett Parker wrote:
On 09 Aug 15:01, Chris G wrote:
I send (some) E-Mail direct to my home server machine using SMTP, I used to do this using a sub-domain of my domain isbd.net which is hosted at Gradwell. I added a CNAME record for 'home' to the zone file for isbd.net and gave my static ADSL address as the value for this record.
Thus mail forwarded to 'chris@home.isbd.net' arrived at my home server machine (subject to NAT forwarding and firewall of course) and was delivered by postfix to user chris.
I now have a dedicated domain for my home server(s) and I'm struggling to get things working.
The new domain is zbmc.eu, I have set up the zone file at the domain hosting as follows:-
imap 10800 IN CNAME access.mail.gandi.net. www 10800 IN CNAME zbmc.eu. smtp 10800 IN CNAME relay.mail.gandi.net. pop 10800 IN CNAME access.mail.gandi.net. blog 10800 IN CNAME blogs.vip.gandi.net. webmail 10800 IN CNAME agent.mail.gandi.net. @ 10800 IN A 84.45.228.40 @ 10800 IN MX 10 mws.zbmc.eu. mws 10800 IN CNAME zbmc.eu.MX pointing to a CNAME is a violation of the DNS policy, MX records should *always* resolve to A records, not CNAME records.
OK, so that's plain wrong, thank you.
You can (in your setup, though it's not what I'd do), use: @ 10800 IN MX 10 zbmc.eu.
That's probably what I'll do initially at least.
(Most of this is unchanged from the default setup of course)
A default setup would *not* have the MX pointing to a CNAME.
You can't tell what it points at since the MX records point to names 'out there' that you have no control over (usually other dedicated servers at the ISP which, of course, shouldn't be CNAMEs).
The 'www' CNAME entry is working fine, going to www.zbmc.eu shows my web pages (or more my lack of web pages!).
I'm not at all convinced that I have the MX record right yet though, nor am I convinced that I actually need that 'mws' CNAME record. Could I just set the MX record to:-
@ 10800 IN MX 10 zbmc.eu.Yes, you can. I wouldn't. I'd setup: mail 10800 IN A 84.45.228.40
How does this differ in essence? Apart from adding another name for the same 'machine' I can see little that it adds?
Can one of the alug gurus elucidate please.
... and do I *need* a second MX (backup) record or will the sending SMTP server just back off and try again if my server is down for a short while?
There's very very rarely a need for a secondary MX record, it's only really of use if you're going to be offline on the primary MX for > 1 day and the TTL of your MX record is set to a long time, otherwise, you just change the MX record during downtime. Other mail servers will queue nicely for you for (usually) up to 3 days, or generate bounces to the senders.
Yes, that was what I had surmised from comments I have seen elsewhere.
Personally, I wouldn't be squeezing SMTP data over a ADSL line, I don't trust BT (or the LLUs) that far... My mail sits outside my home connection on a VM that I can access from anywhere (via imap), and post through from anywhere (using smtp and authentication on the submission port), and I usually use mutt directly on there (unless I want to sign things, etc, then I use the magic mutt config on my laptop instead, as I tend to use ssh as the transport for the imap stream, thus using my ssh key that I've got ssh-agent and a passphrase for, rather than having to give mutt my imap password).
You're doing what I used to do. I used to run mutt on a shell account at my hosting service. I do find that mutt over IMAP is (relatively) slow and clumsy compared with mutt and a real 'unix' mail spool though which is why I have moved to my present setup.
I have two ADSL connections with different ISPs so, as long as the physical connection doesn't get killed (which means I'm stuffed anyway) I can get to my mail. In addition I 'spool' my incoming mail to a system at the hosting service in parallel with sending it to my home system so if I really screw things up (not a *rare* event) I can still get to see my mail.