I haven't done anything like a local Debian repository or a full Debian mirror quite yet. I have however been reading Debian-Administration.org which as a sysadmin, seems to be one of the nicest down to earth places for Debian & Linux admin info. Appropriate articles are How manage a partial mirror with low bandwidth or Question: Manage updates of more then one machine?.
I might as well let you in on my summer project. I hope to setup a local package mirror this summer since I will be setting up a small office LAN for a local church. The church is expected to "go live" around sept 1. I expect to use to a variety of Linux distros. Probably ClarkConnect 3.1 (3.1 to be released soon) for the firewall & proxy which is based on Centos 4. The church is not qualified as a residence so it will have to get business class broadband cable or DSL. It costs at least double if not closer to triple per month, but I don't see any way around that. The upside is that they will get a bigger upstream capability.
Centos 4 is based off the freely available source code packages of RedHat Enterprise Linux 4. I use & administrate RHEL2.1/3 systems at my job. RedHat has setup RHEL 3 & 4 with a support life of at least 5 years. Just like the Debian, Centos is community based & they will be around for a a long time. The full price of RHEL4 for a small or medium business is no big deal as it comes with support. A new startup non-profit lke a church can't afford to drop big money on software so Centos4 is good compromise between enterprise grade Linux & free community Linux. So I will probably use Centos 4 for email, file sharing & printing.
Then I will use Debian 3.1 for workstations and perhaps any other server need that might arise. Sounds like a lot of servers but really only 2 or 3 with 1 as a spare. The workstations will be older PCs (approx 6 years old) running either KDE, IceWM or xfce as RAM & CPU permits.
The church admin assistant (secretary) will run a Debian Linux box. The youth leader (older teens & college age) will probably have a Debian Linux box. The pastoral staff already have their own Windows or Apple Mac laptops. Trying to get them to switch would be a major undertaking so they will stay on whatver platform they are on now. I am not worried about windows viruses or exploits since I will lock down each windows laptop, make the user a non-administrative user, & will force automatic patches/updates & virus signatures.
I will let you know my progress in regards to a local Debian package mirror.

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