Your link is internal, this probably is the published article:
and some background info about the selection process:
The trouble is, if you start to build a VPN infrastructure, you might overlook to introduce peer IDs with your first dialup tunnel. After all, it works without. Only later, when you need the second or more dialup tunnel, you will notice that sometimes the tunnel won't come up. But it may be too late to get a peer ID into your Forticlient configs...if not managed centrally.
One workaround might be (see second article) to use different proposals in phase1. They are part of the selection process.
And then use peer IDs for all upcoming new dialup tunnels.
"Kernel panic: Aiee, killing interrupt handler!"