Confusion about F5 internal networking

Hi All,

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I have some confusion around how the F5 Big-IP software is making routing decisions internally. I hope r/networking can help alleviate this frustration.

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I have a Big-IP set up in HA - everything appeared to be working. I had created nodes, with health checks that passed, and pools with those nodes with health checks that passed.

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I then created a virtual server referencing that pool and again the f5 health checks passed.

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However, if I tried to navigate to the IP of the virtual server I wouldn't get a web page response.

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I believe this is because I had no routes in "Network > Routes" and so it was taking mgmt interface by default for the health checks. After adding routes suddenly all the health checks fail (and I still cannot resolve the web page by virtual server IP).

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Trying ping -I mgmt <node_address> works, but as soon as I try to use either of the other "vlans" it fails; ping -I internal <node_address>.

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Curl-ing over management I get the correct html: curl <node_address> --interface mgmt

But again, I don't get the html if I try the internal interface: curl <node_address> --interface internal

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I have both floating IPs and non-floating self-ips on "interface" and "external" vlans.

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I have put a VM on the same subnet where the internal vlan exists (and tagged its traffic in VMWare) and from there I can ping/curl the web servers so I don't think it is a "real" networking problem - it seems to be me not understanding how to get the F5 working.

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Of note, all the self-ips I created on external/internal are ping-able from my desktop so again I think it's not a reconfiguration of the "real" networking in VMware/switches.

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I have followed documentation pretty closely but I think I must be not understand how the f5 handles itself internally...

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Any help or pointers or links to enlightening documentation is very much welcome!

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Cheers!