Aggregate Route vs Generated Route. What's the difference?
I cry back bespeak myself this same inquiry inward my early on juniper days. I would encounter to a greater extent than or less aggregate routes as well as therefore to a greater extent than or less generated routes as well as intend they did the same thing. Well they don't! I'll endeavour to present speedily how they differ
lab# fix routing-options aggregate road 10.1.1.0/24 lab> present road hidden inet.0: 3 destinations, 3 routes (2 active, 0 holddown, 1 hidden) + = Active Route, - = Last Active, * = Both 10.1.1.0/24 [Aggregate] 00:09:28 Reject We tin encounter the road is added but it's rejected. The argue is because both an aggregate as well as generated road demand to have got a contributing or to a greater extent than specific road that forms business office of the aggregate.
By only adding a subnet inside that aggregate every bit an interface ip that aggregate volition travel activated. Let's see
root@lab> present configuration interfaces ge-0/0/0 | display set set interfaces ge-0/0/0 unit of measurement 0 menage unit of measurement inet address 192.168.1.15/24 root@lab> present road 10.1.1.0/24 extensive inet.0: 5 destinations, 5 routes (5 active, 0 holddown, 0 hidden) 10.1.1.0/24 (1 entry, 1 announced) TSI: KRT in-kernel 10.1.1.0/24 -> {} *Aggregate Preference: 130 Next hop type: Reject Address: 0x8f3a584 Next-hop reference count: 2 State: <Active Int Ext> Age: 32:13 Task: Aggregate Announcement bits (1): 0-KRT AS path: I (LocalAgg) Flags: Depth: 0 Active AS path list: AS path: I Refcount: 1 Contributing Routes (1): 10.1.1.8/30 proto Direct As you lot tin encounter the 10.1.1.8/30 locally connected road is a contributing route. The next-hop yet is reject. The master copy utilization for an aggregate road is to salve routing tabular array infinite inward a router as well as likewise shield the network from road flaps.
Now let's have got a await at a generated road amongst the same ip's.
root@lab> present configuration routing-options | display set set routing-options generate road 10.1.1.0/24 root@lab> present road 10.1.1.0/24 inet.0: 5 destinations, 5 routes (4 active, 0 holddown, 1 hidden) + = Active Route, - = Last Active, * = Both 10.1.1.8/30 *[Direct/0] 00:27:55 > via ge-0/0/1.0 10.1.1.9/32 *[Local/0] 00:27:55 Local via ge-0/0/1.0 So why is the generated road non showing upward inward our routing tabular array you lot may ask? The employment hither is that a generated road needs a next-hop as well as inward our configuration for interface ge-0/0/0 it is setup every bit a multiaccess network as well as non a signal to signal link amongst a next-hop. This is 1 of the requirements for a generated route, at that spot needs to travel a next-hop for the contributing network. If nosotros add together a static road nosotros should travel fine.
root@lab> present configuration routing-options | display fix fix routing-options static road 10.1.1.50/32 next-hop 10.1.1.10 root@lab> present road 10.1.1.0/24 extensive inet.0: 6 destinations, 6 routes (6 active, 0 holddown, 0 hidden) 10.1.1.0/24 (1 entry, 1 announced) TSI: KRT in-kernel 10.1.1.0/24 -> {10.1.1.10} *Aggregate Preference: 130 Next hop type: Router, Next hop index: 551 Address: 0x934c2e0 Next-hop reference count: 5 Next hop: 10.1.1.10 via ge-0/0/1.0, selected State: <Active Int Ext> Age: 6:07 Task: Aggregate Announcement bits (1): 0-KRT AS path: I Flags: Generate Depth: 0 Active Contributing Routes (1): 10.1.1.50/32 proto Static We tin straightaway encounter nosotros have got a contributing road as well as likewise our generated road has a next-hop. If nosotros have a package for a subnet inside the 10.1.1.0/24 network as well as it is non an exact-match for the host road nosotros created of 10.1.1.50/32 therefore the package volition yet travel forwarded to 10.1.1.10.
root@lab> present road 10.1.1.20 inet.0: 6 destinations, 6 routes (6 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both 10.1.1.0/24 *[Aggregate/130] 00:08:29 > to 10.1.1.10 via ge-0/0/1. 