How to Change FEC Mode on FS S5850 Series Switch?
In the world of networking, the FEC (Forward Error Correction) mode plays a crucial role in ensuring reliable and error-free data transmission. For users of the S5850 Series switch, understanding how to change the FEC mode is essential for optimizing network performance. This blog post will provide you with step-by-step instructions on how to change the FEC mode on the S5850 Series switch, along with important considerations to avoid link failures.
Step 1: Accessing the Command Line Interface (CLI)
To begin, you need to access the Command Line Interface (CLI) of the S5850 Series switch. This can be done by using a terminal emulation program or directly connecting to the switch via a console cable.
Step 2: Navigating to the Interface Configuration Mode
Once you have accessed the CLI, you will need to navigate to the interface configuration mode. Enter the following command:
S5850-24XMG# configure terminal
S5850-24XMG(config)# interface eth-0-26
In this example, we are assuming that you want to change the FEC mode for interface eth-0-26. Replace "eth-0-26" with the appropriate interface number for your specific configuration.
Step 3: Selecting the FEC Mode
After entering the interface configuration mode, you will need to specify the FEC mode you want to use. The S5850 Series switch supports three FEC modes: baser, none, and rs.
- Baser: This mode is supported on 50G, 40G, 25G, and 10G interfaces. It is recommended for those interfaces.
- None: This mode disables FEC entirely.
- RS: This mode is supported on 100G, 50G, and 25G interfaces.
To select the FEC mode, use the following command:
S5850-24XMG(config-if)# fec <mode>
Replace `<mode>` with your preferred FEC mode, such as "baser," "none," or "rs."
Step 4: Considering Link Failure (Link Down)
It is crucial to understand that changing the FEC mode inconsistently across interconnected devices can result in link failures or link downs. This can disrupt network connectivity and lead to service interruptions. To avoid such issues, it is recommended to ensure consistency in FEC mode configuration between connected devices. For example, when connecting the S5850 Series to a Mellanox ConnectX-5 NIC, the FEC mode of the 100 ports on the S5850 Series Switch needs to be changed to RS in order for the link between the S5850 Series Switch and the Mellanox ConnectX-5 NIC to establish.
Step 5: Saving the Configuration
After selecting the desired FEC mode, it is essential to save the configuration changes to ensure they persist across reboots. Use the following command to save the configuration:
S5850-24XMG# copy running-config startup-config
This command will save the changes to the switch's configuration file.
The following is the complete command to change the FEC mode to RS on the S5850-24XMG:
S5850-24XMG# configure terminal
S5850-24XMG(config)# interface eth-0-26
S5850-24XMG(config-if)# fec ?
baser set baser FEC(support on 50G/40G/25G/10G interface)
none set none FEC
rs set rs FEC(support on 100G/50G/25G interface)
S5850-24XMG(config-if)# fec rs
Conclusion:
Changing the FEC mode on the S5850 Series switch is a straightforward process that can significantly impact network performance and reliability. By following the step-by-step instructions outlined in this blog post and ensuring consistency in FEC mode configuration across interconnected devices, you can avoid link failures and maintain seamless network connectivity. Remember to save the configuration changes to ensure they are applied consistently.
