Hi everyone,
1)Virtual chassis protocol factors two things in computing the shortest path from rooted PFE to target PFE.
a) bandwidth
b) hop count.
https://www.oreilly.com/library/view/junos-enterprise-switching/9780596804244/ch04.html
From the above link:
When all interfaces have the same bandwidth, as is the case here, the SPF result is effectively based on hop count.
This is what I understand:
SPF first factors in bandwidth in computing the shortest path, if tie, it then considers the hop count to compute the shoretst path from " rooted " PFE to target PFE.
Is my understanding correct?
2) VCCP uses ISIS protcol .
Cisco implementation uses default metric of 10 for all ISIS enabled links. It does not matter if the link is 10 G or 1 G, this metric is then used to compute the shortest path.
In JUNOS' implementation , do we have default value too, regardless of the link bandwidth just like we see in Cisco?
Below I see metric value of 15 , I am not sure if this the deafult value or if this value was computed using bandwidth as we see in OSPF?
https://www.juniper.net/documentation/en_US/junos/topics/reference/command-summary/show-virtual-chassis-protocol-database-mx-series.html#jd0e517
From the above link:
user@host> show virtual-chassis protocol database member 0 detail
member0:
--------------------------------------------------------------------------
001d.b510.0800.00-00 Sequence: 0x9f5, Checksum: 0x5b2b, Lifetime: 116 secs
Neighbor: b0c6.9abf.6800.00 Interface: vcp-1/3/0.32768 Metric: 15
b0c6.9abf.6800.00-00 Sequence: 0x9f8, Checksum: 0x326e, Lifetime: 117 secs
Neighbor: 001d.b510.0800.00 Interface: vcp-5/0/0.32768 Metric: 15
Thanks and have a nice weekend!!