Description:

For analysis and monitoring purposes it is useful to check the CPU and memory load of network devices. On a LANCOM R&S®Unified Firewall this can be done via the CLI command htop.

This article describes how the current CPU and memory load on a Unified Firewall can be monitored via the CLI command htop.

Requirements:

• LANCOM R&S®Unified Firewall with LCOS FX as of version 10.3
• SSH-Client, e.g. PuTTY

Procedure:

1) Connect to the Unified Firewall with an SSH client and login with the user gpadmin.

2) Enter the command htop and press the <Enter> button.

3) The tool htop is structured as follows:

• The digits on the upper left (in this case 1 - 4) represent the logical CPU cores and their load. The load is displayed in different colors.  
  • Blue: Low priority processes
  • Green: Normal priority processes
  • Red: Kernel processes
• Mem represents the memory load. The load is displayed in different colors.  
  • Green: Used memory
  • Blue: Buffer
  • Yellow: Cache (the cache is freed when the memory load increases)
• Swp represents the virtual memory. The used virtual memory is always displayed in red.
• Tasks displays the amount of processes, Threads and currently running threads (in this example there are 101 processes, which are divided into 179 threads, but only one thread is running).
• Load average displays the CPU load for 1, 5 and 15 minutes. The values have to be multiplied by 100 in order to obtain the percentages (in this case the CPU load in the last minute was 22 %).
• The Uptime displays the running time of the Unified Firewall since the last reboot.
• Below the individual processes and threads are shown with with various information, e.g. CPU load (CPU%), Memory load (MEM%) and virtual memory (VIRT).