Forum Discussion
Sarah_258804
Cirrus
CirrusCan I change the default ephemeral ports that the F5 uses for health monitoring?
Currently I see that my F5 is reaching out to the servers in my server pools on low ephemeral ports for health monitoring. For example, I have a health monitor for DNS so that the F5 reaches out to the DNS servers to ensure that DNS is working properly. The source port coming from the F5 has a huge range from sometimes 7000 up to 65535. We are trying to standardize the ephemeral ports used in our datacenter to use the standard Microsoft ephemeral ports, 49152 - 65535 for ACI filtering.
Can I manually change which ports the F5 uses to send requests on? I know we are currently doing this with Linux servers, so I'd like to do it with the F5s as well.
ekaleidoSame as you would on a linux host:
echo "49152 65535" > /proc/sys/net/ipv4/ip_local_port_range
Sarah_258804I ran that command on each F5 but am still seeing it try to communicate on 43900 and lower. Do I need to perform a system reboot for the changes to take effect, or something of that nature?- ekaleidoThat will apply after a reboot. Try, sysctl -w net.ipv4.ip_local_port_range = 49152 65535
- Sarah_258804Received this error: error: "net.ipv4.ip_local_port_range" must be of the form name=value error: Malformed setting "=" error: "49152" must be of the form name=value error: "65535" must be of the form name=value
ekaleido_26616Cirrocumulus
Same as you would on a linux host:
echo "49152 65535" > /proc/sys/net/ipv4/ip_local_port_range- Sarah_258804I ran that command on each F5 but am still seeing it try to communicate on 43900 and lower. Do I need to perform a system reboot for the changes to take effect, or something of that nature?
- ekaleido_26616That will apply after a reboot. Try, sysctl -w net.ipv4.ip_local_port_range = 49152 65535
- Sarah_258804Received this error: error: "net.ipv4.ip_local_port_range" must be of the form name=value error: Malformed setting "=" error: "49152" must be of the form name=value error: "65535" must be of the form name=value