Offline Mail Queues w/ Mac OS X?

Zorton asks: "After switching to Mac OS X (10.2) for my primary work/play environment I started to customize the system as I would a Linux or BSD system. One of the first things I wanted to tackle was getting mail into the machine and enabling offline mail queuing (as this is a laptop that roams quite a bit). After installing Fink I was happy to see some of my favorite MTAs available. However I was disappointed to discover there seems to be no mechanism similar to /etc/network/if-up.d (or similar). I spent a bit of time poking and prodding the system but the best I could come up with where some library functions listed on Apple's Developer Connection website. Has anyone tried to configure offline mail queues under Mac OS X 10.2? If you have how did you handle telling the MTA to transfer the mail you have queued up?"

Comments

Umm, it's already there...

[itwerx]

I'm not sure what you're needing to do but the Mail app which comes bundled with OSX does all that out of the box. The mail spools for each user are under their respective /user/joeblow/Library/Mail/Mailboxes They're even in standard 'nix spool format!
If you need to use a different app just point it to the right folder and let OSX do the rest...

Re:Umm, it's already there...

[phyxeld]

If you want to tie events to changes in your location, ie when you select something different from AppleMenu->Location->..., have a look in /System/Library/SystemConfiguration/Kicker.bundle/ Resources/ (removing the slashcode-added space...)
XML files and shell scripts powering the mac location manager... never thought I'd see the day :)

Re:google cache of the man page....

[austad]

Out of the box, sendmail is not set up correctly on OS X, at least in 10.2.

I ripped it out and installed Postfix on my iBook instead. I pointed Mail.app at localhost for it's SMTP server, and even when I'm offline, my mail will queue up. However, the only reason I did this is because my ISP's SMTP server sucks, and I wanted to bypass it.

Mail.app will already do offline queues, so you really don't need to do anything special. If it can't send a message, it will tell you, and you just click the "Send Later" button.

Re:google cache of the man page....

[foniksonik]

Here's a few links to help out those who want to set up sendamil correctly (with bind et al thrown in for good measure).

http://www.macosxhints.com/article.php?story=200 20 825230925806

Pretty basic, but a quick start...

http://www.sial.org/sendmail/macosx/8.12.2-jagua r/

More technical and in depth for those who know and care.

And of course you can also google for "sendmail os x 10.2" like I did and find other resources.

Mail.app out box

[foniksonik]

Mail.app will queue your outbound mail in a standard way... throws them in to the 'Out' box and will send them first opportunity. You could also try out eudora which has all kinds of nifty extras.

Don't forget to set up rules in Mail.app for cc to yourself or whatever. Finally there are lots of 'hidden' features to Mail... that are standard on other mail progs... like bcc, that you just have to turn on via one of the menus.

If you are using ppp, pppoe, or similar...

[Graff]

I do know that pppd calls a script every time its connection goes up or goes down. You may be able to write a script to do your mail transfers with this script.

When the connection is made it calls the shell script at: /private/etc/ppp/ip-up

When the connection is broken it calls the shell script at: /private/etc/ppp/ip-down

If you don't use ppp or pppoe (or anything else that uses pppd) then maybe there are similar scripts in other places. Hope this helps.

Re:google cache of the man page....

[austad]

Sendmail is the devil, install postfix. Postfix is both faster and much easier to administer (postconf -e command, instead of editing the evil sendmail.cf file by hand). You will have to install some extra packages to get it to compile (like pcre, and the latest Berkeley DB), but it's worth it. Plus, postfix has a much shorter history of security issues, and runs as a non-priveledged user to reduce the chance of something really bad happening if a new exploit is discovered.

Just google for "postfix os x 10.2" to find install instructions.

How do I know postfix is better? I built several large mail clusters for a large online financial site using sendmail, qmail, and postfix. Postfix well outperformed the other two (the versions in the last year anyway, qmail used to be the fastest). And with a large number of machines, postfix was a dream to administer.

Hello? Cron?

[kwerle]

Shell scripting was invented for a reason. Don't copy this script and expect it to work. But do copy the idea.

crontab:
* * * * * /somepath/checkping.zsh

/somepath/checkping.zsh:
#!/bin/zsh
if ([ test -e /tmp/connected.txt ])
then
if (ping -c 1 www.apple.com)
then
# we are already up
else
# we went down
rm /tmp/connected.txt /somepath/wentdown.sh
fi
else
if (ping -c 1 www.apple.com)
then
date > /tmp/connected.txt /somepath/wentup.sh
else
# we were already down
fi
fi

diffrent ideas

[Zorton]

thanks for everyones input

I think the underlying problem i'm having is the lack of any ip-d up script or anything like that. It seems to be obvious now after reading some of the comments posted, that the short term solution would be to use Mail app or point something else towards Mail.app's mail dir. I still would like to find out how the location manager does it's thing (Under the apple menu -> location). The API for it seems to be very well documented and perhaps I will end up coding something similar to a interface up script. In the meantime all I will do is install postfix and have it default upon startup to offline mode. Then i'll run a cron job about every minute or to check for up interfaces that have come up (ifconfig -u, and check the routing tables). Not quite as elegant as i've done in the past on a debian system using qmail but should get the job done. I think with a system like that I could grab e-mail from my pop box using another cron job (fetchmail?), and have a offline mail queue ready to go.

What do you think? Has anyone taken a closer look into the location manager's inner workings? I find it difficult to believe apple didn't provide any provision for advanced configuration of the interfaces (changing the MAC address or perhaps the MTU based on diffrent locations and options).

Thanks

Re:diffrent ideas

[Brownian Motion]

Try reading this nice article about updating SAMBA when your ip changes. Since it shows you how to run a shell script when your ip changes, hopefully this will allow you to do what you want.

http://www.culater.net/osd/samba/samba.html

There's some info from Apple: http://developer.apple.com/techpubs/macosx/Network ing/SysConfigOverview926/index.html?http://develop er.apple.com/techpubs/macosx/Networking/SysConfigO verview926/SysConfigOverview926c.html

And it's not what you want, but if you want to change locations from the command line, you need to look at the nice command /usr/sbin/scselect. (Take a look in /usr/sbin and /usr/bin for a bunch of nice Apple Command line tools. Rare if it has a man page though.)

What I want to be able to do is to be able to run a script when my laptop wakes up. Still haven't found something nice for that. I can run a program in the background all the time that gets notified of power events, but I'm sure that Apple already has something running which will do this. (I want to use a command line tool to sniff for wireless access points, and depending on what is found, switch my location. I can do it all...if I run the script manually, I just want it to run automatically on wakeup.)

Re:diffrent ideas

[aeijdenb]

/System/Library/Frameworks/SystemConfiguration.fra mework/Versions/A/Headers/SCNetwork.h

SCNetworkCheckReachabilityByName
or
SCNetworkCheckReachabilityByAddress

will both "determines if the given network host/node name is reachable using the current network configuration."

They will NOT cause a modem user to automatically dial.

Re:diffrent ideas

[klez23]

in case you didn't see the previous post above, i thought i'd restate that there IS a mechanism just like ip-d-up. it's a script called /etc/ppp/ip-up (and there's a corresponding /etc/ppp/ip-down). They probably don't already exist, but you can create them. I've got it chmod 700. My ip-up reads as follows (note that "sendmail" & "mailq" actually refer to my postfix executables):

#!/bin/sh

#send queued messages (really uses postfix)
Q=`/usr/local/sbin/mailq`
if [ "$Q" != "Mail queue is empty" ]; then
logger -t $0 sending queued messages
/usr/local/sbin/sendmail -q
fi

#update dyndns entry
/etc/ppp/ip-up.ddclient $*

Some ressources from O'Reilly

[paulio]

Check out Mac OS X for Unix Geeks from O'Reilly
http://www.oreilly.com/catalog/mosxgeeks /
and
Top Ten Mac OS X Tips for Unix Geeks
http://www.oreillynet.com/pub/a/mac/2002/10 /22/mac forunix.html

Er, configure sendmail?

[MrChuck]

I've been using sendmail for over a decade.

UUCP and PPP meant spool up mail, send it periodially.
UUCP ran periodically (cron), when PPP started up, a startup script would run a sendmail queue runner.

The only difference here is (1) determining when you are "on the net" via ethernet or wireless and (perhaps) (2) using TLS and SMTP AUTH to allow you to send ANY TIME you are on ANY net - you authenticate yourself to a machine on the net and use TLS to encrypt the transaction. Or setup an IPSec connection to your server. Or use UUCP over SSH (scary, but I've done it).

Configure sendmail in "queue only mode" and treat it like an occasionally connected machine. This is basic (for mail).

Re:Will this handle changes to outgoing mail serve

[phyxeld]

I change locations a lot. I use entourage and although I use the location manager which handles the network changes fine , I have to change smtp servers manually to send mail depending on where I am. I haven't found a way around this with switching locations. Does this suggestion help solve my problem?

Can you ssh to a server near any of your smtp servers?
If so, that would be the ideal method. All my accounts use localhost:2525 as the smtp server, and I have an ssh command something like ssh user@sshhost -C -v -L 2525:smtphost:25 -L 1101:pophost:110 to tunnel everything. If your ssh host does SSH2 (protocol version two, not version two of the software) you can use the -f -N options to background it, which makes it easy to start and stop from a location-triggered shell script. (and naturally, you'll want to use localhost:1101 as your pop server now, so that too will be encrypted)

Doing unencrypted pop and smtp from a laptop is never a good idea. Even if you're careful, eventually you'll probably leave your mail client open while you use your machine within range of some random wireless network, and then you'll be sending your cleartext password over not just the internet but also the public airwaves...

In addition to the security, another benefit to using ssh tunnels for pop and smtp is that your mail client can only get packets out to the internet when the ssh tunnel is up. It doesn't know the name of the actual internet servers, and if you killall ssh, connections to localhost2525 and localhost:1101 are simply refused and you've made no noise at all on the network. And another benefit is that you can have a local port open from behind any firewall (ie, use -R 8080:localhost:80 in your ssh command and http://sshhost.yourisp.net:8080/ will have your local webserver on it). I often use this for testing websites from behind the firewall at work.

Ok, I could go on more, but the point here is that ssh is damn cool.