Extended VLAN stops working on HCX Network Extension
search cancel

Extended VLAN stops working on HCX Network Extension

book

Article ID: 325157

calendar_today

Updated On:

Products

VMware HCX VMware Cloud on AWS

Issue/Introduction

To identify the root cause and fix the HCX network extension issue if it is failing due to "segment Overlap".


Symptoms:

Extending a vLAN segment from source(on-prem) to the destination(VMC) using HCX NE may fail though it might seem to work initially. 

Un-extending and re-extending the network does not fix the issue. Re-deploying the Network Extension (NE) appliance also does not help.

 


Cause

It is most likely caused due to the vLAN segment at the source overlaping with segment in the destination, 

You may find a similar error like the below in the HCX app.log.

<DATE> <TIME> UTC [NetworkStretchService_SvcThread-177, j: 605ffd88, s: 73327777, , TxId: XXXX-XXXX-XXXX-XXXX-XXXX] ERROR c.v.v.h.n.i.AbstractJobInt- NetworkStretchJobs workflow prepareCloudNetwork failed. Error: Error creating NSX-T Segment. Address <IP>/24 overlaps with Segment path=[/infra/tier-1s/cgw/segments/hcx-ne-<ID>] that has subnet <IP>/23. 

<DATE> <TIME> UTC [NetworkStretchService_SvcThread-177, j: 605ffd88, s: 73327777, , TxId: XXXX-XXXX-XXXX-XXXX-XXXX] ERROR c.v.v.h.n.i.AbstractJobInt- Exception in NetworkStretchJobs:ExtendNetworkWorkflowInt. Reason : Error creating NSX-T Segment. Address <IP>/24 overlaps with Segment path=[/infra/tier-1s/cgw/segments/hcx-ne-<ID>] that has subnet <IP>/23.

<DATE> <TIME> UTC [NetworkStretchService_SvcThread-177, j: 605ffd88, s: 73327777, , TxId: XXXX-XXXX-XXXX-XXXX-XXXX] ERROR c.v.v.h.n.i.NetworkStretchJobInt- Error encountered in Network Stretch job java.lang.RuntimeException: Error creating NSX-T Segment.

Address <IP>/24 overlaps with Segment path=[/infra/tier-1s/cgw/segments/hcx-ne-<ID>] that has subnet <IP>/23.

<DATE> <TIME> UTC [NetworkStretchService_SvcThread-177, j: 605ffd88, s: 73327777, , TxId: XXXX-XXXX-XXXX-XXXX-XXXX] ERROR c.v.v.h.n.i.NetworkStretchJobInt- Error encountered in Network Stretch job

Resolution

In order to resolve this issue please change the VLAN segment either on the on-prem side or the segment on the SDDC cloud side, so that it does not overlap.

(For example: In this scenario, the you may edit the vLAN segment from <IP>/24 to <IP>/23 (on-prem).


Additional Information

Impact/Risks:

Production impact as the connectivity between on-prem VMs to VMC VMs will be down.


Powered by Wolken Software