ALERT: Some images may not load properly within the Knowledge Base Article. If you see a broken image, please right-click and select 'Open image in a new tab'. We apologize for this inconvenience.

Unable to resolve fully qualified host name. Exiting with HTTP 500 server error '00-0016'


Article ID: 5450


Updated On:


CA Single Sign On Secure Proxy Server (SiteMinder) CA Single Sign On SOA Security Manager (SiteMinder) CA Single Sign-On


Seeing errors in the webagent.log:

[CSmHttpPlugin.cpp:406][ERROR][sm-HTTPAgent-00030] Unable to resolve fully qualified host name. Exiting with HTTP 500 server error '00-0016'.
[CSmResourceManager.cpp:158][WARNING][sm-AgentFramework-00480] HLA: Missing resource data. 


Also seeing following in the webagenttrace.log:

[CSmHttpPlugin.cpp:399][CSmHttpPlugin::ProcessResource][0000000000000000000000001234567a-345602-1234040f-ff02b700-2345678a1234][][][][][][Resolved HTTP_HOST: ''.]
[CSmHttpPlugin.cpp:5518][Entered CSmHttpPlugin::ResolveFQServerName sHost: ][][][][][][][]
[CSmHttpPlugin.cpp:5600][CSmHttpPlugin::ResolveFQServerName: isIP][][][][][][][]
[CSmHttpPlugin.cpp:10195][CSmHttpPlugin::DoDNSLookup ][][][][][][][Entered Function server:, port: ]
[CSmHttpPlugin.cpp:10264][CSmHttpPlugin::DoDNSLookup Error: ][][][][][][][Name or service not known]
[CSmHttpPlugin.cpp:10280][CSmHttpPlugin::DoDNSLookup ][][][][][][][Leaving Function]
[CSmResourceManager.cpp:94][CSmResourceManager::ProcessResource][0000000000000000000000001234567a-345602-1234040f-ff02b700-2345678a1234][][][][][][SM_WAF_HTTP_PLUGIN->ProcessResource returned SmExit.]
[CSmResourceManager.cpp:160][CSmResourceManager::ProcessResource][0000000000000000000000001234567a-345602-1234040f-ff02b700-2345678a1234][][][][][][Plugins did not collect required resource data.


The 00-0016 error is being reported because a request is being made using the IP Address instead of the FQDN, and the Agent is unable to resolve the IP to a FQDN.



Web Agent 12.x SPx


Please use FQHN instead of an IP address.

SiteMinder uses cookie (SMSESSION) to manage user sessions and for single sign-on purpose this need to be set with a domain.


If the initial request must be made with IP address, then you can set "ForceFQHost=Yes" in the Web Agent ACO.

Set ForceFQHost = yes (default: no)

The ForceFQHost parameter uses Reverse DNS Lookup to resolve a FQHN and redirect to that resolved address.

This would work only if the reverse dns lookup is configured correctly.


In case if you have a loadbalancer/proxy as frontend, please ensure you work with its vendor to ensure FQHN is passed on in the HTTP Host header to the backend webserver integrated with web agent.