Should I install Diagnostic Agent on managing system itself ?

Question

Dear All,
  I am using a solution manager as an managing system .
  Should I install the Diagnostic Agent on the managing system , too ?
  My solution manager is 7.01 EHP1 SPS22, I find  there exist a directory /usr/sap/SMD , so it seems the Disgnostic Agent is installed during the solution manager installation . But in the Work Center -> Root Cause Analysis -> Agent Administration , it returns a "service cannot be reachable " error, 
"URL https://<solution manager host >:8000/webdynpro/dispatcher/sap.com/tcsmdnavigation/StandaloneApp call was terminated because the corresponding service is not available.
  And in the http://<solution manager host>:50000/smd , managed system -> setup wizard , I choose the solution manager SID , and next, it show the SMD agent hasn't been found.
  I re-installed the SMD agent , but the result is the same, and I've tried to install the Diagnostic Agent 7.11 and still the same.
Anyone encounter the same problem as me ??
Thanks.

Answer 1

Hi, David,
  In Solman_Setup , The initial and Basic configuration are finished without error ( green light).
  And in managed system configuration , configure system, the first step check prerequisities failed with red light; the detail error messages is as below :
It seems some kind of service not activated in SICF , but not for sure.
Service cannot be reached
What has happened?
URL https://sapsolmgr.centurydsp.com:8000/webdynpro/dispatcher/sap.com/tcsmdnavigation/StandaloneApp call was terminated because the corresponding service is not available.
Note
The termination occurred in system SM2 with error code 404 and for the reason Not found.
The selected virtual host was 0 .
What can I do?
Please select a valid URL.
If you do not yet have a user ID, contact your system administrator.
ErrorCode:ICF-NF-https-c:000-u:SAPSYS-l:E-i:SAPSOLMGR_SM2_00-v:0-s:404-r:Notfound
HTTP 404 - Not found
Your SAP Internet Communication Framework Team
Thanks for your reply.
Enddy.