RTR assumes a default 25% of free memory as low-water mark. If the available free memory is less than this value, then probes will not be created. This low-memory water mark can be changed with the "rtr low-memory" command.
If your router has 64 MB, you need 16 MB (25%) for rtr to work, by default. I guess you can change this with 'rtr low-memeory" command
See the following link for more information on the command:
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...