As Jeter said, make sure that you have routes set up between the central office and the remote office. I presume that you are trying to ping all remote sites from the central site. If the PIX is set up corretly so that we can take that out of the equation for now and concentrate on getting the routing right, then you need to ensure that either RIP or EIGRP is running correctly or that you have your static routes set up correctly. Do all of the remote offices just connect to the central office or are they meshed with other remote offices?
If they are meshed (ie. you might have one interface connecting to the central office and one connecting to another remote office offering an alternative route)then a routing protocol such as RIP or EIGRP should be used to advertise routes. If one link should fail then the alternative route will be advertised. However, if each office only connects to the central office then static routes can be used as each router (apart from the central one) only has one outbound interface and therefore can use a default route to route all external traffic out of.
The central router could then have a static route for each remote network. For example, interface 1 might point to 10.5.2.0/24, interface 2 might point to 10.5.3.0/24 etc.. If this is set up correctly then you should be able to ping all remote offices from the central office. If you can't then I suggest that you take a look at the routing tables and see what's going on. Also, make sure that your remote routers have a route pointing back (should be the default route).
Good luck.
Chris.
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Chris Andrew, CCNA
chrisac@gmx.co.uk
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