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Updated at June 10, 2025
Aggregated prefixes (aggregates)
To automatically announce new subnets to Cloud Interconnect, you can use aggregated subnet prefixes (aggregates). With aggregates, you only need to set up prefix announcements once. From then on, you can add new subnets to your VPC without contacting support.
For example, when setting up
Routing Instance
, you can specify announcements for aggregated IPv4 prefixes formatted as follows:ru-central1-a [10.128.0.0/16] ru-central1-b [10.130.0.0/16] ru-central1-d [10.140.0.0/16]
If later you create a subnet with the
10.128.15.0/24
prefix in this network in theru-central1-a
availability zone, it will automatically be available via Cloud Interconnect because the10.128.15.0/24
subnet belongs to the already announced address space,10.128.0.0/16
.