On Wed, Mar 04, 2015 at 02:42:44PM -0500, Jeffrey Haas wrote: > > There is a presumption that it may be possible for the I2RS agent to > restart. Given that a number of I2RS operations are likely to be built > using multiple interactions with the agent, it's necessary to understand > what state the agent may be in with regard to last-reset. A simple but > unscalable way to implement this is to preceed each operation with a > get/get-config to verify the state of the system prior to sending in the > next I2RS operation. >
If this is a problem (which I am not sure), then send a get/get-config before each edit operation won't buy you much since the agent can still restart inbetween. > What is likely more stable is simply knowing whether > the system is in the same state as when you last interacted with it. > > A version numbering system of some sort, whether system-wide or potentially > as part of some models (perhaps even just I2RS models) would be sufficient > to provide such a checkpoint. > > An example of the problem space this would address presuming three > operations must be completed to accomplish a given I2RS goal, "A B C". > If the agent crashes after B has been done, C may either complete with no > errors, or may fail before the setup state for A and B are no longer in the > system. The simple solution is to make "A B C" one atomic edit. > An analogous mechanism in SNMP to address such issues are discontinuity > objects. No, not really. Discontinuity objects help with monitoring, not so much with sets. SNMP folks invented TestAndIncr (RFC 2579), which is used to implement so called spin-lock objects. While this can be made to work, I am not sure I would recommend this approach. While this method allows to detect that edits were conflicting, it makes the clients responsible to clean up the mess. /js -- Juergen Schoenwaelder Jacobs University Bremen gGmbH Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany Fax: +49 421 200 3103 <http://www.jacobs-university.de/> _______________________________________________ i2rs mailing list [email protected] https://www.ietf.org/mailman/listinfo/i2rs
