Difference between tmsh modify node "session user-enabled" and "state user-up"?

It is somewhat confusing isn't it. I'd have thought that the

tmsh modify ltm node ‘name’ up

would have done the job. Does it? The default is down.

From the tmsh reference guide: http://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/bigip-tmsh-11-4-0.html.

session user-enabled;

"Establishing a session with a node is establishing the ability of the client to persist to the node when making new connections. When a node is session disabled, clients that have already established sessions with the node may create new connections, but a client that has not already established a session may not create a new one (or make a connection which would create a new session). This feature is used to gently drain connections from a node, typically as part of a maintenance operation. The default value is user-enabled."

state user-up

"Specifies the current state of the node. Use user-down to indicate that the node may not handle any new connections. Use user-up, after using user-down, to indicate that the node may accept new connections."

Ah yes, thanks for reading the manual for me. I'll have to make a note of that!

My script uses this line:

tmsh modify ltm node 1.2.3.4 session user-disabled

...in order to drain stop a node before the node is rebooted each month. For some reason the script using the 'user-enabled' command quit working and the nodes would never show a green status. Ultimately I figured out that issuing the 'state user-up' fixed my problem because at some during testing the 'state user-down' command must have been issued.