in the /etc directory you will find the "crontab" file. This is used by the cron scheduling service to run programs or commands at specified times. While you can edit this file directly, it will be overwritten each time you change something in the server manager, so use that file for monitoring only, actually make changes to the templates.
You will find the crontab templates in the /etc/e-smith/templates/etc/crontab directory (I think this was slightly different in pre 6 releases?)
I chose to put my commands into the 00setup file, so that they appear at the beginning of the crontab file - you can probably use any of the files in that directory though...
I then used the following command to drop all but my own MAC address
20 00 * * * root iptables -I FORWARD -j DROP -m mac --mac-source ! {MAC addy}
20 00 * * * root iptables -I INPUT -j DROP -m mac --mac-source ! {MAC Addy}
IF you want all blocked I think you can probably sustitute the -m mac with all or similar, but lets face it, given that the "!" inverts the command, (as in it drops all but the specified MAC) all you need to do is enter a MAC addy not on you LAN.
The bit at the beginning of the line controls the crontab scheduling. In this instance it tells it to execute the command at 20 past midnight. The "root" tells it to run as root (miss this out and it will not work)
For more details on crontab scheduling see
http://www.mkssoftware.com/docs/man1/crontab.1.asp Using this you can schedule the commands to occur at different times at weekdays / weekends, different every day etc etc... It is flexible if a wee bit convoluted.
To reinstate I simply put the following:
30 12 * * * root iptables -D FORWARD -j DROP -m mac --mac-source ! {mac addy}
30 12 * * * root iptables -D INPUT -j DROP -m mac --mac-source ! {mac addy}
Which switches all back on at half past midday.
I found that I needed to block both the forward and input chains, as IRC and the like seems to work differently to HTTP....
I am sure somebody else will have a far more elegant solution than mine, but if you want any more help on this ugly duckling I am happy to give it
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