Hi Jim, You must be aware that OpenSAF works in a distributed system, and that it might be some delays in delivering messages between nodes due to some reasons like network congestion, service processing large amount of messages, emulate broadcasting messages, etc. In your case, if you are using notifications (which comes from NTF service) for syncing data/performing actions between nodes, I would recommend to switch to appliers, which are part of IMM.
Since there could be some delays in message deliveries in a distributed system. In your case, it's obvious that NTF worked a bit faster than IMM was sending message for committing data. I will cite Anders Bjornerstedt which explains a lot of the problem you face: " The imm "can guarantee" that a CCB than has been ack'ed as commited to the OM ccb-client (or an OI-applier), has been committed in fevs order over all nodes. In particular it means that it has been commited at the node where the reply was provided. If you send messages between nodes based on that commit, then to ensure that a receiver at a remote node receives that mesage in fevs order, then you need to use a fevs ordered messaging service, e.g. admin-operation. Note an admin-operaton request goes over fevs, but the reply does not. This means that the receiver of the request will receive the request in fevs order. But the receiver of the reply is only guaranteed that a reply is returned after the request has ben procesd in fevs order. " Thanks, Zoran -----Original Message----- From: Anders Widell [mailto:[email protected]] Sent: den 10 oktober 2017 18:39 To: Carroll, James R <[email protected]>; [email protected] Subject: Re: [users] EXTERNAL: Re: notification vs model updates Hi! I am referring to the interface described in Section "MULTIPLE APPLIERS (4.2)" in the IMM README, please see https://sourceforge.net/p/opensaf/code/ci/develop/tree/src/imm/README regards, Anders Widell On 10/02/2017 05:25 PM, Carroll, James R wrote: > Hi Anders, > > Thank you for your response. Can you clarify what you mean by "IMM applier > interface"? > Is this the object management API (OM-API), or the object implementer API > (OI-API)? > Or is it some other interface? > > Thanks. > > Jim > > > -----Original Message----- > From: Anders Widell [mailto:[email protected]] > Sent: Monday, October 02, 2017 8:35 AM > To: Carroll, James R (US) <[email protected]>; > [email protected] > Subject: EXTERNAL: Re: [users] notification vs model updates > > Hi! > > This is expected when considering the current OpenSAF design. The reason is > that IMM and NTF use different communication protocols; IMM uses a form of > group communication based on extended virtual synchrony, whereas NTF uses > simple point-to-point communication. > > To avoid this problem, you can use the IMM applier interface instead of NTF > notifications. > > regards, > > Anders Widell > > > On 09/22/2017 03:24 PM, Carroll, James R wrote: >> Hi, >> >> We are using OpenSAF 5.2, and have observed the following behaviors: >> >> 1) We receive a Notification for an update >> >> 2) When we query the IMM for the updated information, the model has not >> been updated >> >> 3) If we wait, and query the IMM again, the model now has the correct >> information. >> >> This happens infrequently, but has been observed a number of times. >> Can you clarify this behavior? Is this normal or expected? >> >> Thanks. >> >> Jim >> >> --------------------------------------------------------------------- >> - >> -------- Check out the vibrant tech community on one of the world's >> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot >> _______________________________________________ >> Opensaf-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/opensaf-users >> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Opensaf-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/opensaf-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Opensaf-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/opensaf-users
