net.ipv4.ip_local_port_range

You can see current settings by executing the command:

# sysctl net.ipv4.ip_local_port_range
net.ipv4.ip_local_port_range = 32768	61000

You can change this setting by executing the command:

# sysctl -w net.ipv4.ip_local_port_range="1024 65000"
net.ipv4.ip_local_port_range = 1024 65000