FQDN ephemeral nodes will not be deleted - pool member still online

You don't need a DNS monitor. F5 makes a DNS resolution based on the configuration you setup for that. It should remove, or replace, the node/member if not getting that from the DNS query. The only situation that may cause delay here to remove is if there is a connection open to that member, as I am not sure if deletes and close the connection, or waits to finish or time out.

Have a look in this solution:

https://support.f5.com/csp/article/K47726919

If I remove the DNS entry, the ephemeral node still exist.

have you tried to enable monitor logging? is there anything useful in log file (/var/log/monitors/)?

 tmsh modify ltm node  logging enabled

If I remove the DNS entry, the ephemeral node still exist.

have you tried to enable monitor logging? is there anything useful in log file (/var/log/monitors/)?

 tmsh modify ltm node  logging enabled

by default, we are not monitoring nodes, only pool member.

i might misremember. i thought i did see /var/log/monitors without health monitor assigned.

anyway, i did a bit test your scenario here and it seemed okay. i am on 13.1.0.1.

// has record

[root@ve13a:Active:In Sync] config  tcpdump -nni 0.0 -s0 port 53
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on 0.0, link-type EN10MB (Ethernet), capture size 65535 bytes
13:06:35.935529 IP 200.200.200.11.52454 > 200.200.200.16.53: 55672+ A? www.acme.local. (32) out slot1/tmm1 lis=
13:06:35.936526 IP 200.200.200.16.53 > 200.200.200.11.52454: 55672*- 1/1/1 A 200.200.200.200 (81) in slot1/tmm1 lis=

[root@ve13a:Active:In Sync] config  tmsh list ltm node
ltm node _auto_200.200.200.200 {
    address 200.200.200.200
    ephemeral true
    fqdn {
        interval 60
        name www.acme.local
    }
}
ltm node testnode1 {
    fqdn {
        interval 60
        name www.acme.local
    }
    state fqdn-up
}
[root@ve13a:Active:In Sync] config  tmsh list ltm pool
ltm pool testpool1 {
    members {
        _auto_200.200.200.200:80 {
            address 200.200.200.200
            ephemeral true
            fqdn {
                name www.acme.local
            }
        }
        testnode1:80 {
            fqdn {
                name www.acme.local
            }
            state fqdn-up
        }
    }
}

// no record

[root@ve13a:Active:In Sync] config  tcpdump -nni 0.0 -s0 port 53
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on 0.0, link-type EN10MB (Ethernet), capture size 65535 bytes
13:08:35.940014 IP 200.200.200.11.52454 > 200.200.200.16.53: 22762+ A? www.acme.local. (32) out slot1/tmm1 lis=
13:08:35.940793 IP 200.200.200.16.53 > 200.200.200.11.52454: 22762 NXDomain*- 0/1/0 (83) in slot1/tmm1 lis=

[root@ve13a:Active:In Sync] config  tmsh list ltm node
ltm node testnode1 {
    fqdn {
        interval 60
        name www.acme.local
    }
    state fqdn-up-no-addr
}
[root@ve13a:Active:In Sync] config  tmsh list ltm pool
ltm pool testpool1 {
    members {
        testnode1:80 {
            fqdn {
                name www.acme.local
            }
            state fqdn-up-no-addr
        }
    }
}