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ZAHIDHASEEB's avatar
ZAHIDHASEEB
Icon for Nimbostratus rankNimbostratus
Nov 26, 2019
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Does F5 load balancer intelligent in case of ports are down

Does F5 load balancer intelligent in case of ports are down? Suppose, if there are 2 servers behind F5 load balancer and in case application got down(who is listening on port 80) on one server so ho...
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  • Heinrichm5's avatar
    Heinrichm5
    Nov 27, 2019

    It depends on where you've added your health monitor and how you've configured it

    Typical scenario: you want the other ports to remain active after a single port has stopped responding

    You need to have configured several pools, each with their own port, eg

    PoolA:

    name: http_pool

    members: 10.10.10.10:80, 10.10.10.12:80

    monitor: tcp_half_open (no port denfined in the monitor settings)

     

    PoolB

    name: https_pool

    members: 10.10.10.10:443, 10.10.10.12:443

    monitor: tcp_half_open (no port denfined in the monitor settings)

     

    If 443 stops responding 80 will still work. Same if it is the other way around.

     

    The monitor can be configured in the GUI

    Selecting a monitor: Local Traffic > Pool > Select your pool > find the monitor in the right window and move it to the left

    Creating a custom monitor: Local Traffic > Monitor > Create

     

ZAHIDHASEEB's avatar
ZAHIDHASEEB
Icon for Nimbostratus rankNimbostratus

Currently I am reading the referred link regarding the monitoring actions or behavior which you shared in last post.

As per my understanding in case the provided service/port is down on node behind F5 LB then the node will be marked as down and F5 LB will not entertain the new connections until the port on node UP again. Now here I have another concern. Actually my node hosted an application which receives connections requests on different ports means different services are LISTENING on different ports. Suppose if a single port become down then complete node will be marked as down and the rest of ports will also not be able to facilitate the new connections

 

Second point. Does the monitor configuration setting is available thru GUI. Please share any technote if available

Heinrichm5's avatar
Heinrichm5
Icon for Altocumulus rankAltocumulus
Nov 27, 2019

It depends on where you've added your health monitor and how you've configured it

Typical scenario: you want the other ports to remain active after a single port has stopped responding

You need to have configured several pools, each with their own port, eg

PoolA:

name: http_pool

members: 10.10.10.10:80, 10.10.10.12:80

monitor: tcp_half_open (no port denfined in the monitor settings)

 

PoolB

name: https_pool

members: 10.10.10.10:443, 10.10.10.12:443

monitor: tcp_half_open (no port denfined in the monitor settings)

 

If 443 stops responding 80 will still work. Same if it is the other way around.

 

The monitor can be configured in the GUI

Selecting a monitor: Local Traffic > Pool > Select your pool > find the monitor in the right window and move it to the left

Creating a custom monitor: Local Traffic > Monitor > Create