Image: Forward Error Correction in Practice
Some reading on FEC (Forward Error Correction):
3 instances where you need to give a FEC!
1) E-Series with 25GbE for iSCSI
If you’ve got E-Series with 25GbE for iSCSI. And the
ports don’t come up, you don’t even get a link light, even though you can see a
light coming out the SFP, opposite side to a light going in from the LC/LC
cable (so not a cable transposition error), then it might be FEC.
I wasn’t getting any connection until the network guy
disabled FEC on the ports.
2) 25Gb card connections on a A300/FAS8200 MCIP
using Cisco 3232 switches
From the MCIP guide:
If your AFF A300 or FAS8200 system is configured using
25-Gbps connectivity, you need to set the Forward Error Correction (FEC)
parameter manually to off after applying the RCF file.
The RCF file does not apply this setting if the cable
connecting the controller module is not inserted into the port.
This task must be performed on all four switches in
the MetroCluster IP configuration.
Steps:
Set the fec parameter to off on each 25-Gbps port, and
then copy the running configuration to the startup configuration:
a. Enter configuration mode:
config t
b. Specify the 25-Gbps interface to configure:
interface
interface-ID
c. Set fec to off:
fec off
d. Repeat the previous steps for each 25-Gbps port on the
switch.
e. Exit configuration mode:
exit
Do a copy run start to save the changes.
3) On
StorageGrid SGA6060 with 25G ports when connected to Cisco
You might need to
change the autonegotiation to auto, using ethtool.
First time is when Pre-Grid environment is booted, login
and run ethtool against ports eth3-6.
After reboot that is part of joining grid, login again and
now run ethtool against hic1-4.
Fixed in 11.3 or in a hotfix.
Comments
Post a Comment