There are 2 issues: causing dialing, and logging the result. I don't know of a management solution that would do this automatically, although a script could likely be written to do the same thing. It would be "manual", I suppose, but still effective. The sequence would be to telnet to a 1750 (I assume there is access to it by means other than the DDR), ping to cause dialing, note whether it's successful or not, clear the line and close the telnet connection. Move to next device.
Another way (not necessarily better) would be to configure Dialer Watch for some non-existent route, which can be a statically configured route that is propogated by the 5350 or some other box. When you want to test the DDR links, you remove the static route, which should ultimately cause the remotes to dial (no interesting traffic required). The 5350 could note who dials in and connects, log that to a syslog server for more crunching to see who did not connect. However, since you have 540 remotes, you really don't want them all dialing at the same time. So you can either set up Dialer Watch delay timers differently per group of boxes, or setup multiple phantom routes with one route watched by a group of 1750's, and remove the static route one at a time for testing purposes.
