I was wondering if I could pick some admin heads here as I have a HUGE project I have been tasked with.....

I am asking here since I will be basing everything on Centos, and want it to all play nice together. If anyone feels this is straying off topic, please just reply off list. I do not want to be the cause of one of those threads.

I have 3 offices, 1 in Canada, 2 in Mexico. We are currently investigating connectivity options (still no results yet), but I suspect one of the mexican sites will be very limited.

I need to setup the typical office setup, but need to get the following figured out. I personally do not have experience in this type of network (all my past experience comes from a centralized office, one location, or a multi office with services all based in their respective locations).

So because The connectivity is probably limited (in our mexican offices), I will need to take that into consideration (obviously).

Our head office has a 10mb full duplex fiber feed, but we also have equipment in data centers.

What I need in the end is:

- exchange like functions IE Global address book, shared calenders, etc (looking at scalix, or could keep my existing email server - very happy with it, and just setup a LDAP server and a CalDAV server - still investigating this one though).

- Funambol with various connectors to push email and calendars to blackberries and iphones.

- vpn (openvpn) - mostly just the head office though

- collaborative / project management environment (looking at alfresco - sharepoint alternative)

- monitoring (nagios)

- helpdesk (glpi with ocs for inventory management)

- file sharing (samba)

- remote file backups (probably just rsync into a dedicated backup machine in a data center)

- access to all services (probably - still waiting back from the higher ups) from all locations

So my first thought is that my preference it to keep as much at a data center as possible due to security, temperature control, connection reliability, etc. Due to my inexperience with some of these products, (IE Scalix,etc) I am kind of wondering what the best way or topology is to do this is.

So at a brief first thought I kind of envisioned this:

- scalix,  Funambol, alfresco, nagios (also one in my office as backup), backup box collocated in the data center providing it can be locked down adequately, and still provide the needed services to all 3 offices.

- in each office a samba file server, vpn server.

Due to the probable connectivity issue with the remote offices (one is literally in the desert at a work site), I did not think a constant inter-office VPN was the way to go, Or even securing the main data center services with VPN (unless I could build it right for speed).

However I guess I could lock down the data center services with VPN, and create a constant connection between head office and the data center, and allow the other offices to connect via individual vpn connections as needed.

Thoughts? Just looking for a general broad overview, or some software recommendations if anyone from experience has a recommendation that is possibly better than the software I had outlined here.

Dnk