how is the route table of the azure private peer of an expressRoute created and how do i flush 1 entry

Question

We have a wrong entry in our routing table due to a misconfiguration of a bastion subnet.

We changed the subnet, but the route remains.

Answer 1

@86842230 ,

Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

I am afraid I did not understand your question, can you please elaborate.

Route advertisement is automatic in an ExpressRoute scenario.

• See : How are virtual networks advertised on ExpressRoute private peering?
• This means, every subnet will be advertised to the peer via the ExR.

Are you saying that the BGP routes advertised or from a different range than that of the VNETs' ?

Cheers,

Kapil

Answer 2

@86842230 ,

I am afraid I don't understand what you mean by "corrected the mistake by removing the faulty network from the bastion subnet configuration the address space is still part of the is still part of the Peered virtual network address space of this subnet"

• Are you saying that you made changes to the Address space of a Peered Virtual network?
• And this updated Address space is not reflecting in the BGP?

NOTE : When you update the address space for a Peered virtual network, you need to sync the virtual network peer for each remote peered virtual network

See : Modify the address range prefix of an existing address range

• Can you please "Sync" the Virtual Network Peering from both end and let us know?
• This should update the address ranges across the VNETs and in turn, BGP Advertisements

Cheers,

Kapil