I tried discovering a linux box and deploying agent, But I see below error. 
My WinRM service is running perfectly fine on the management server.
My error is:
“”The WinRM client cannot complete the operation within the time specified. Check if the machine name is valid and is reachable over the network and firewall exception for Windows Remote Management service is enabled.””
When I telnet to port 1270, the connection fails. There we have an issue. Very simple
Run this to open the port on linux box.
iptables -I INPUT -p tcp -m tcp --dport 1270 -j ACCEPT 
Ok now that your ports are open, now when you try to discover and try installation, you see “”access denied.””

When I see in the event Log of RMS, I see event ID 1002
Log Name:      Operations Manager
Source:        Cross Platform Discovery
Date:          12/16/2011 8:19:18 AM
Event ID:      1002
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      CHBH25062627-1.dc250626.local
Discovery of linux failed with the following error:
Installed Agent failed to initialize properly.
Access is denied.
Event Xml:
So it lies beyond 1270 port. Something that did a trick. Run below.
This could be that partially installed agent are not allowing the agent to be installed. See that installation fails at Validation step. I tried to remove the partially installed agent. Agent  was any way running on the Linux box. Try below step
rpm -e scx
rm -rf /etc/opt/microsoft/scx
step Now, start the discovery and install of agent through console.
You see a happy face…

-Chandan Bharti