Unable to login to rstudio via pam

Hi Team,
We installed rstudio in redhat linux server. The users are able to login to server via ssh. But are unable to login to GUI on port 8787. The error is :
ERROR : Invalid method TRACE requested for uri: /; LOGGED FROM: bool rstudio::core:http:AsyncServerImpl::Onheaderparsed
rserver-pam[2448]: pam_unix(rstudio:auth): authentication failure ; logname= uid=0 euid=0 tty= ruser= rhost= user=test123
rserver-pam[2448]: pam_unix(rstudio:auth): authentication failure ; logname= uid=0 euid=0 tty= ruser= rhost= user=test123
rserver-pam[2448]: pam_unix(rstudio:auth): authentication failure ; logname= uid=0 euid=0 tty= ruser= rhost= user=test123
ERROR system error 2 (No such file or directory) [description: user not found., user-value:3123232]; OCCURRED AT rstudio::core:Error rstudio::core:system

Please help to resolve this issue.

Also let me know what are the basic rpm files needed to setup rstudio server.

Thanks
Sugunakar