What command(s), softwares/tools can I used to measure the convergence time in Quagga running an OSPF network? Thanks :)
You can use a common non-Quagga-specific recipe:
Fire a continuous ping test over the main path established by OSPF.
Disrupt the main path.
Wait until OSPF restores connectivity for ping.
Record how much time elapsed between steps 2 and 3.