3640854 - "503 service unavailable" error in outsidediscovery.log during ConfigureOutsideDiscovery to SAP Focused Run

When attempting to register the host into SAP Focused Run (FRUN) using ConfigureOutsideDiscovery, a "503 Service Unavailable" error appears in the OutsideDiscovery.log. Upon reviewing the sapstartsrv.log, the following errors are observed: 

[Thr 139696400750336] Tue Aug  5 10:59:54 2025
[Thr 139696400750336] *** ERROR => ConfigureSLDDestination: Destination host XXX cannot be resolved. SLDReg Create Failed [OutsideDiscoveryPlugin.cpp 160]
[Thr 139696400750336] *** ERROR => Webmethod ConfigureOutsideDiscovery failed: ConfigureSLDDestination: Destination host XXX cannot be resolved. SLDReg Create Failed [saphostcontr 3367]

[Thr 139696388933376] Tue Aug  5 11:53:05 2025
[Thr 139696388933376] *** ERROR => Operation::ExecuteNextCommand(): Command OS Command terminated with errorcode 254 [Operation.cp 357]
[Thr 139696388933376] *** ERROR => Operation [id=5B1733D7C4FD1FD09CB4E9DC6F17FC33]: Command execution failed [Operation.cp 468]
[Thr 139696388933376] *** ERROR => Operation::ExecuteNextCommand(): Command OS Command terminated with errorcode 254 [Operation.cp 357]
[Thr 139696388933376] *** ERROR => Operation [id=5B1733D7C4FD1FD09CB4E9DC6F181C33]: Command execution failed [Operation.cp 468]

[Thr 139696388933376] Tue Aug  5 11:55:15 2025
[Thr 139696388933376] *** ERROR => Operation::ExecuteNextCommand(): Command OS Command terminated with errorcode 255 [Operation.cp 357]
[Thr 139696388933376] *** ERROR => Operation [id=5B1733D7C4FD1FD09CB4E9DC6F183C33]: Command execution failed [Operation.cp 468]

SAP Focused Run

503 service unavailable, outsidediscovery.log, ConfigureSLDDestination, network resolution issue, FQDN, SAP Focused Run, Simple Diagnostic Agent, gateway connection, sapstartsrv.log, DNS configuration. , KBA , SV-FRN-INF-SDA , Simple Diagnostic Agent (SDA) , Problem