NOTE: All Redhat Linux parameters described over the sections below are not supported by Symantec, they have been technically evaluated however for best direction or support, please contact the vendor directly.
It is recommended to disable auto-negotiation on the network interfaces and set the appropriate speed/duplex. You can use ethtool or mii-tool to set this depending on the network interface that you are using however the change will not persist a reboot.
To set the speed/duplex permanently you have to edit the ifcfg-ethX scripts, usually located under /etc/sysconfig/network-scripts.
For 100Mbps, append this line: ETHTOOL_OPTS="speed 100 duplex full autoneg off"
For 1000Mbps, append this line: ETHTOOL_OPTS="speed 1000 duplex full autoneg off" If the line shown above fails to negotiate, then you can use: ETHTOOL_OPTS="speed 1000 duplex full autoneg on"
For best network performance, you can append the following lines to your /etc/sysctl.conf file:
# APPEND STARTS HERE # Controls whether core dumps will append the PID to the core filename. # Useful for debugging multi-threaded applications. kernel.core_uses_pid = 1
# Controls TCP timing and port availability. net.ipv4.tcp_keepalive_time = 1800 net.ipv4.ip_local_port_range = 1024 65000 net.ipv4.tcp_fin_timeout = 30
# Kernel Receiver Backlog (Default is 300) net.core.netdev_max_backlog = 2000
# Increase TCP max buffer size setable using setsockopt() net.core.rmem_max = 16777216 net.core.wmem_max = 16777216
# Increase Linux auto-tuning TCP buffer limits # min, default, and max number of bytes to use # set max to at least 4MB, or higher if you use very high BDP paths net.ipv4.tcp_rmem = 4096 87380 16777216 net.ipv4.tcp_wmem = 4096 65536 16777216
# recommended to increase this for 1000 BT or higher net.core.netdev_max_backlog = 3000 net.ipv4.tcp_fin_timeout = 30 net.ipv4.tcp_keepalive_time = 1800 net.ipv4.tcp_synack_retries = 3