Hello,
there is a command available that specifies the order in which multiple dialer strings are used:
dialer order
Basically, there are three options: sequential, round-robin, and last-successful.
Sequential - Always starts dialing the first dial string configured in a list of multiple strings, and continues to the next dial string when a call fails. This keyword allows dial string order to be prioritized, and is the default
round-robin - Always starts dialing using the dial string that follows the most recently used dial string. If no calls have previously been made, the dialer uses the first dial string. When a call fails, the dialer tries the next dial string until all dial strings have been tried. This keyword allows calls to be shared equally among the configured dial strings. However, if the dial strings are associated with multiple ISDN B channels on the same remote device, a call may be placed to bring up a second B channel without trying to call the number associated with the first B channel
last-successful - Always starts dialing using the most recently successful dial string, and continues to the next dial string in a list when a call fails. This keyword reduces the time needed to find a dial string that successfully completes a call when the dial strings are not likely to be equally successful
Check the comamnd reference for more info:
dialer order
http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123cgcr/dial_r/dia_d1g.htm#wp1125720
HTH,
GP
