So, Multipath wasn’t designed for this exact use case (more so where you have two active links presented to ZT), but you could try using active-backup in your local.conf
like so:
{
"settings":
{
"defaultBondingPolicy": "custom-active-backup",
"policies":
{
"custom-active-backup":
{
"basePolicy": "active-backup",
"failoverInterval": 10000
}
}
}
}
This will increase ambient traffic (to measure links) but it should cause a faster switch to your new link.
Let me know if you have any other questions on this.
EDIT: Fixed typo in example