[VMC on AWS] Failed to pair on-premise Site Recovery Manager (SRM)

Products

• VMware Cloud on AWS

Issue/Introduction

Best practices regarding DNS to pair on-premise SRM to VMC SRM

Symptoms:
SRM site pairing fails 

SRM logs:

2019-12-17 04:20:03,821 [srm-reactive-thread-1] WARN  com.vmware.srm.client.reactive.impl.PromiseIm
pl 3448735673820395734 ########-####-####-####-########be7b probeServices - Function 'com.vmware.dr
.client.shared.pairing.ProbeServicesRequestHandler$$Lambda$532/752947785@4e0a973f' failed.
java.lang.IllegalArgumentException: host
        at org.apache.commons.lang.Validate.notEmpty(Validate.java:321)
        at com.vmware.dr.client.shared.pairing.utils.CertInfo.<init>(CertInfo.java:32)
        at com.vmware.dr.client.shared.pairing.ProbeServicesRequestHandler.lambda$null$157(ProbeSer
vicesRequestHandler.java:357)
        at com.vmware.srm.client.reactive.impl.PromiseImpl$ApplyCompletion.complete(PromiseImpl.jav
a:244)

srms = {
         LsppService {
         _serviceNameDefault = vCenter DR service
         _serviceVersion = 8.2.0.14761908
         _endpoints = [LsppService.LsppServiceEndpoint {
            protocol = vmomi
            type = com.vmware.dr.vcDr.configure
            url = https://vsphere_srm.xxxxxxxx.local:5480/configureserver/sdk
            }, LsppService.LsppServiceEndpoint {
            protocol = vmomi
            type = com.vmware.dr.extApi
            url = https://vsphere_srm.xxxxxxxx.local:443/drserver/vcdr/extapi/sdk
            }, LsppService.LsppServiceEndpoint {
            protocol = vmomi
            type = com.vmware.dr.vcDr
            url = https://vsphere_srm.xxxxxxxx.local:443/drserver/vcdr/vmomi/sdk
            }]
         _type = vcDr
         _siteId = default-site
         _id = 74755a30-####-####-####-########a33
         _nodeId = 212ab706-####-####-####-########d92
         _product = com.vmware.dr
         _attributes = {vmodlVersion=/drserver/vcdr/vmomi/drversion.xml, supportedVmodlVersions=/drserver/vcdr/vmomi/drserviceversions.xml, extensionKey=com.vmware.vcDr, vcInstanceUuid=########-####-####-####-########5893}
         _ownerId = SRM-74755a30-####-####-####-########[email protected]
         }
   }

Cause

This is caused because of the ( _ ) in the hostname. Example : vsphere_srm.xxxxxxxx.local

Resolution

Remove the special character from the hostname and replace it with the supported character. Review Microsoft's documentation regarding the allowed special characters in the DNS: Naming conventions inactive directory