A Telnet monitoring tool allows users to establish a connection with a remote device, and check whether a particular device or application is available. Users can connect to a device using Telnet to access resources, monitor metrics, and transfer or receive useful data.
Telnet is a protocol used to communicate or interact with remote servers over the TCP/IP network. It enables text-based communication. Network administrators typically use Telnet to monitor remote computers or access files from them using HTTP or FTP.
Telnet is one of the simplest protocols used in client-server models. It allows users to connect multiple devices (terminals) to a remote server. Telnet does not demand an advanced or powerful device; it requires only a basic computer with a text-based interface to establish communication.
In the client-server model, the server is a remote computer that provides services to a client. The client is a hardware device that uses Telnet to interact with the server for specific purposes. For example, if you want to change a server’s password, you can log in to that computer using Telnet, and request to change the password.
Telnet also checks whether a port is open or closed. The firewall installed by the user on a client device will often block the port used by Telnet. Since Telnet cannot access a port that’s blocked by a firewall, you should disable the firewall before using Telnet.
By default, OpManager monitors devices using SNMP. To monitor non-SNMP devices like computers running Linux, you can use the Linux machine’s command line interface (CLI) for communication through Telnet.
OpManager offers Telnet monitoring software and monitors non-SNMP devices using either SSH or Telnet. Let's say you want to monitor a Linux server: for this, you have to configure the server’s credentials in OpManager, and choose Telnet as the protocol.
Once this is done, OpManager will be able to discover the Linux server, and it will automatically associate the default monitors as per the device template, ensuring that the performance metrics of the devices are monitored.
Likewise, OpManager will monitor any type of CLI-based device, like routers, switches, or firewalls, using Telnet. Before configuring the terminal’s credentials, you must ensure that the required port for the terminal is open.
Servers are important components that facilitate seamless operation of clients, so monitoring your servers is essential. But monitoring can be challenging if the server is remote. OpManager ensures the health and performance of CLI-based devices by monitoring using Telnet.
The major metrics that can be monitored using Telnet are:
This information enables you to optimize processes and ensure peak device performance.
OpManager supports Windows, Solaris, and Linux server machines and monitors the availability and response time of the Telnet service. To enable a connection with a remote server, you have to configure the server’s credentials in OpManager.
You can use OpManager to monitor a remote server for performance metrics, and use that information to decide whether to terminate unwanted processes and stop them from consuming resources. After you’ve configured the remote server’s credentials, OpManager will be able to automatically log in to the remote server and execute system commands. OpManager parses the output after execution and stores the relevant information about CPU and memory utilization.
IT admins generally use OpManager to Telnet a remote device at constant intervals for availability. Though this method is useful, it does not completely ensure the continuous uptime of the device, because a network fault may occur at any point of time, even right after the device is checked for availability.
This is why OpManager uses Telnet to monitor a remote server/device for health and performance. It gathers data about various parameters and stores it as reports for future analysis and reference. The reports serve as historical data and help network administrators understand the nature of performance at a granular level.
These intuitive reports are especially useful for remote devices, as it enables users to assess network faults proactively and prevent them.
OpManager not only monitors remote terminals using Telnet, but it also offers fault management options to restore faulty terminals. The nature of each fault varies, and OpManager enables you to handle each of them appropriately.
A big challenge faced by IT admins while monitoring remote devices is not being updated about device faults and downtime. OpManager uses Telnet for monitoring CLI-based devices and informs you about faults and issues occurring on remote devices.
You can configure threshold values for important metrics. Every time a device violates a particular threshold, an alarm will be raised in OpManager. Based on the threshold value, you can configure the severity of an alarm.
You can also be notified via SMS/email about alarms by configuring the notification profile. Sometimes, users may miss out on important updates on alarms, which can lead to serious consequences. To avoid this, OpManager offers the Alarms Escalation feature, which notifies you when critical alarms go unnoticed.
For certain faults, you may already know which actions need to be performed, for example, over-consumption of disk space. For this, you can automate the corrective actions by creating a Workflow that checks the size of a folder, and if it exceeds the given limit, you can choose to delete the older files to free up disk space.
On the other hand, if you happen to encounter faults for which you need assistance, you can raise them as tickets in tools like ServiceDesk Plus or Slack to enable collaboration. This way, you can speed up the fault recovery process.