t.petch <[email protected]> wrote: > YANG (with NETCONF) is designed for writing configuration and reading > everything else, and does an excellent job at it. Trouble is, for me, > that configuration doesn't mean what I think of it as; it means, in the > YANG context, what you might put in through the CLI and it excludes > everything else, such as data learnt via a protocol.
This is true, but more for NETCONF than for YANG. I think it has been clear from the start that I2RS probably needs some (hopefully minor) extensions to NETCONF and/or YANG, should we choose to use these technologies. Also, I think it has been pretty clear that what is missing is a way to identify writable data that is not configuration (in the NETCONF/YANG sense). > In practice, this means that the YANG model comes in twin sets, one of > read-write configuration and one of read-only not-configuration (as can > be seen in the current I-Ds that the netmod WG is producing) Correct. This reflects how it usually works on devices; most routers and similar equipment has a "config mode CLI" and "show commands"; a linux box has config files and various ways of reading and writing operational state (/proc, direct apis...) These are different structures with different syntax and semantics. (SNMP tried to combine the two into one, but this turned out to be problematic.) > with no > formal way in YANG of relating the one to the other. So if you want > e.g. the routing table, the host software has to know where to look and > how to combine the pieces to produce a coherent picture (and then you > cannot edit most of it). > > So if I2RS never wants to write anything to a router, YANG is fine; if > I2RS is only producing a Information Model (and ignoring whether or not > data is read-only or read-write), and not moving on to an > implementation, then YANG is fine. > > Rather, as Andy Bierman said at IETF89, likely I2RS would need an > extension to YANG, a new sub-statement for all data objects, semantics > not too clear but designed to separate out the not-configuration, learnt > via a protocol, 'editable-state' (and in doing so, making it > read-write - but still 'config false'). > > Yes, YANG allows for such extensions but it seems to me that I2RS would > then be getting YANG++ (and NETCONF++), once the necessary work has been > done. You can call it YANG++ and NETCONF++, but the fact is that these things can be done today, without having to revise the YANG or NETCONF specs, by using the current extensibility mechanisms. /martin _______________________________________________ i2rs mailing list [email protected] https://www.ietf.org/mailman/listinfo/i2rs
