Argent offers SEVEN options for monitoring UNIX/Linux systems:
- Telnet
- SSH
- UNIX/Linux Secure Agent
- UNIX/Linux Daemon
- UNIX/Linux Shell Script Agent
- SSH Relay Agent
- UNIX/Linux Rule Engine
Each option provides different features and benefits.
Secure Agent-Less Monitoring Options
Telnet
The ArgentXT server establishes connection to the monitored node using the Windows telnet client and default port 23. As telnet communication is not encrypted, this option should generally be avoided.
See Also: Unix Monitoring – Telnet
Secure Shell (SSH)
The Argent XT server establishes a SECURE connection to the monitored node on port 22 using the PuTTY SSH tools PSCP (Secure File Copy) and PLINK (Secure Command Execution). Due to licensing restrictions, PuTTY is not distributed by Argent.
By default, SSH monitoring is a four-stage operation:
-
Copy the monitoring script from the Argent XT server to the monitored node
-
Modify the script file permissions to allow execution
- Remotely execute the monitoring script
- Remove script file from monitored node.
| See Also: | Unix Monitoring – SSH |
| Optimizing SSH | |
Secure Agent-Based Monitoring Options
UNIX/Linux Secure Agent
Argent UNIX/Linux Secure Agent is a platform-specific compiled binary that is installed on the UNIX/Linux Node. The UNIX/Linux Secure Agent runs under the control of the super-server inetd.
See Also: UNIX/Linux Secure Agent
UNIX/Linux Daemon
The UNIX/Linux Daemon is also a platform-specific compiled binary that is installed on the UNIX/Linux Node you want to monitor. The UNIX/Linux Daemon runs independent of inetd and should be used where the use of inetd is considered inefficient or unsecure.
See Also: UNIX/Linux Daemon
UNIX/Linux Shell Script Agent
The UNIX/Linux Shell Script Agent is a cross-platform Bourne Shell script for other UNIX based operating systems such as Mac OS X. The UNIX/Linux Shell Script Agent is included in the UNIX/Linux Secure Agent distribution and runs under the control of the super-server inetd.
See Also: Unix Monitoring – Linux
Load Balancing Options
SSH Relay Agent
The SSH Relay Agent shifts the SSH connection workload from a Windows monitoring engine to a UNIX/Linux machine, which generally make SSH connections more efficient. A Windows monitoring engine sends the Rule (a UNIX/Linux shell script) to the SSH Relay Agent, which then makes the connection to the monitored servers via SSH, executes the Rule, then sends the information back to the monitoring engine. Consider deploying one or more SSH Relay Agents to distribute the load.
See Also: Unix Monitoring – SSH Relay Agent
UNIX/Linux Rule Engine
The UNIX/Linux Rule Engine retrieves its marching orders from the main Argent server, makes SSH connections to the monitored servers, and sends back the results to the main Argent server.
This provides additional fault tolerance, as well as removing the connection load from a Windows monitoring engine. Since each UNIX/Linux Rule Engine initiates the connection to the main Argent server, firewall configuration is also simplified, since you only have to open one port. The UNIX/Linux Rule Engine is analogous to an Argent XT Daughter Engine.
Both the SSH Relay Engine and the UNIX/Linux Rule Engine use OpenSSH, and compared to using PuTTY on Windows Operating Systems, they are more efficient and more robust.