i have searched F5 web site and other resources on the internet for something bothering me which is how to find out which monitor can be associated to a node and which one can be associated to a pool member.
is there any document which describe classification of monitors per type of objects (node/pool member) ??
29-Aug-2021 04:13 - last edited on 24-Mar-2022 01:18 by li-migration
quoting from AskF5 Home >> Knowledge Centers >> BIG-IP LTM BIG-IP Local Traffic Manager: Monitors Reference >> Mo...:
Simple monitoring determines whether the status of a resource is up or down. Simple monitors do not monitor pool members (and therefore, individual protocols, services, or applications on a node), but only the node itself. The system contains three simple monitors, Gateway ICMP, ICMP, and TCP_ECHO.
I think this manual chapter will also answer all possible other questions regarding monitors.
Thank you Daniel for the answer.
i probably wasn't clear enough in my question , i will try to clarify.
in the BIG-IP you can create a lot of kind of monitors, some of them can be associated to a node and others not.
when we are creating a new nodes/pools on the BIG-IP i through web interface or TMSH the TMOS list the supported monitors depending if we are creating nodes or creating pools.
for a deep understanding of monitors and BIG-IP how this selection is done?
hope i have been clearer this time and thank you again
A node does not have a service port assigned, therefore you can assign only simple monitors like ICMP.
A pool member is always node + port, therefore it has a service port. Means you can assign monitors of the kind Active or Passive. For example http oder https.
This what i was thinking too
In this case the port is determined by the monitor, not by the node. Hence you can assign it to a node.
Compare the following monitors:
tcp - has no port assigned, cannot be assigned to a node
tcp_777 - has a port assigned, can be assigned to a node
https - has no port assigned, cannot be assigned to a node
https_443 - has a port assigned, can be assigned to a node
thans a lot Daniel
i understand that but it is more like an assumption based on experience , i cannot find any document explaining precisely this classification
See the section Monitor association with pools and nodes >> Monitor-to-node association
Node-only monitors specify a destination address in the format of an IP address with no service port (for example, 10.10.10.2). Conversely, monitors that you can associate with nodes, pools, and pool members specify a destination address in the format of an IP address and service port (for example, 10.10.10.2:80). Therefore, when you use the BIG-IP Configuration utility to associate a monitor with a pool, pool member, or node, the utility displays only those pre-configured monitors that are designed for association with that server.
Yes, you can say that you will learn this only with experience. But it is also written in the manual.
i have suumrized my tests on the folowing table, my be it can help in the future