split detection virtual chassis

Question

i'm studying juniper virtual chassis and i've lab with following:

can someone explain how split detection works in juniper?

"no-split-detection" is configured on every virtual chassis(Ex3300,Ex3400), there is no mixed mode VC's. now, i want to disable "no-split-detection"(which will enable back split detection). After doing this is what happens to vc's if there is split?

For, example there is 4 member VC :

1) if vc-port broken on Master, does it will cause any issue to VC? as connection is redundant hope there will be no issue, as one of link broken(let say towards Backup) still has redundant connection is there with(linecard), as far as i know there will be no issues? correct me if im wrong

2) suppose, if "Backup" member got failed to boot/dead completely. next linecard will take role as "Backup" or as split detection is enabled and master consider there is split and will push it's own master role to line card?

Note: all members are preconfigured with master-ship priority.

Answer 1

Read this Juniper document titled Understanding Split and Merge in a Virtual Chassis. It explains, when split-detection is enabled (the default), the algorithm's goal is to avoid having two or more different groups of switches remain active after a split.

In your diagram, the stack will behave as expected in both the failure scenarios you outline. Note that, because you have provisioned the switches' stack ID and mastership priority, switches cannot move from linecard to RE role, because you can only configure two switches in RE role.