Is it a good idea to bind the optical fiber with the radio link ?

RouterOS Beginner Basics
1

I would like to establish a connection using 2 links. The first basic one using optical fiber (1.25Gbit), the second backup one using radio link (0.1Gbit). A link will be established between the two CRS326. Will the ordinary bonding of optical fiber with the radio link cause a decrease in performance?

2

Most bonding modes and Tx hashes work best when all bond members have same performance (both bitrate and latency). With your pair of links, I’d go with active-backup mode and set fiber link as primary link. If both links were active at same time, theoretical cumulative throughput would only be 10% higher than of fiber alone …

Alternative to having bond in active-backup mode would be to run RSTP between endpoints and let RSTP disable one of links (default is to disable the slower link), but switchover is likely much longer than in case of bond.

3

Thanks for active backup option.