Yes, there are limits regarding number of devices u can run at the same time which depends on CML version u got and your machine CPU / RAM / Storage resources will limit you as well; CML Personal version lets u use upto 20 Cisco devices (non-Cisco should not count). Re machine resources; well, CML version does not speicify the Max of resources but has list of the Minimum resources u need per type of images. u can see list of this in CML DOc - link attached
Regards, ML
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