I also have done may upgrades on both Windows/SQL Server and Solaris/Oracle systems and have never experienced any loss of custom attributes.
Some of the upgrades do overwrite AST forms thereby losing custom attributes from these forms but these cases are well documented in the upgrade documents and the effects are easy to mitigate. I’d add further that it’s good practice not only to use bespoke namespaces and custom field id’s but also to use attribute names that won’t ever be overwritten should BMC ever decide to add an attribute that you have added (I always add a customer-related prefix, e.g. IBM_WarrantyEndDate). John, could you point to the documentation that states that it is BMC best practice never to add bespoke attributes to BMC classes which is what I understand you are saying. If a new attribute was required for, say, the Computer System class how would you add that in your CMDB such that a user would easily be able to see a Computer System CI with this new attribute data? Of course, if a developer adds a field directly to one of the CMDB forms (eg BMC.CORE:BMC_BaseElement) then that could potentially be affected by upgrades. As we all know, attributes should only be added through ‘legal’ means (Class Manager or CMDB api (eg cmdbdriver)). In the past BMC has extended the CMDB by the use of extension packs (eg for integration with BMC Foundation/Topology Discovery). As far as a future upgrade is concerned the classes and attributes added by these extensions are just the same as bespoke customer classes and attributes. I’ve upgraded such systems also without unexpected loss of attributes. Cheers Peter From: Action Request System discussion list(ARSList) [mailto:arslist@ARSLIST.ORG] On Behalf Of John Doe Sent: 24 July 2011 14:26 To: arslist@ARSLIST.ORG Subject: Re: Adding Custom Attributes to Base Element ** Gentlemen, I have learned, from my own personal experiences, CMDB upgrading success depends very heavily on your environment. That, of course, is only my opinion. Which is based on the facts of every different environment upgrade. I usually don't have many problems with my SQL Server, VM systems. I will certainly grant that. However, it's when your environment is out of this ordinary that you will most likely see the error. Taking a Solaris/Oracle (SPARC) system from 7.5 to 7.6.04 SP1, or a Linux/Oracle (Red Hat) or a Sybase system from 7.5 to 7.6.04 SP1, has (in my experience) erased custom fields added to Base Element. I have filed many cases with BMC over the years for this. Coupling these many cases and others, has resulted in BMC official best practice guidance. You will see this in various Admin guides and white papers. You will find with 7.0/6.3 upgrades, it is a challenge, at best. I do agree that if you have a Sql Server, MS VM 08 system, with a 7.5 or greater CMDB you might be ok. However, I would ensure it is accomplished on a like test environment prior to production installation and everything can be restored back. Not just a VM backup but a DB recovery method also. To instill this, at the end of my post I wrote "your environment and situations will dictate your decisions." Your Post: It sounds like your suggestion would equate to creating a whole new custom CMDB structure in a custom namespace instead of using the BMC one. The way I read it he wants to use many of the classes in the CDM but just needs a few new attributes that apply to all classes. Yes you are correct and that is because it is a BMC best practice. " One of the best practice with regards to customization is having a custom field ID range. Also, whenever you extend the data model, BMC recommends usage of a custom namespace instead of BMC.CORE ." I am simply going by BMC recommendations here. Which are applicable to his requirements. I agree it is the long way around. Your Post: " I am thinking there are a number of people on this list (including myself) who have upgraded with custom attributes in Base Element without any issue. " which I can understand and agree with you on that. However, it is BMC, not I, who have made this a best practice. Likely, because there are many more on the side of bad than good of adding these classes directly to Base Element. I will say, the bad, is these fields surviving during an upgrade. Which is the reasoning behind the best practice. It is why I posted "I know the road you are wanting to go down seems easier right now." I only offer friendly advice from someone who has been down this road every possible way. Thank you Jason for stating the other side of the coin, it is very applicable for that environment. _____ From: Jason Miller <jason.mil...@gmail.com> To: arslist@ARSLIST.ORG Sent: Sunday, July 24, 2011 1:26 AM Subject: Re: Adding Custom Attributes to Base Element ** I am thinking there are a number of people on this list (including myself) who have upgraded with custom attributes in Base Element without any issue. We have taken ours from 7.5 -> 7.6 -> 7.6 p1 -> 7.6 p2 -> 7.6.03 -> 7.6.04 SP1 without any issue. That said I wouldn't be surprised if there would be an issue if you had a CMDB that originated with CMDB version 1 or 2 and tried to bring it up to 7.6.xx. Those were the CMDB learning years and it has come a long way since then. I think you are probably OK if you are starting with a fairly recent version of the CMDB. I don't see how adding a custom class outside of BMC.CORE is going to help Alejandro accomplish his goal. It sounds like your suggestion would equate to creating a whole new custom CMDB structure in a custom namespace instead of using the BMC one. The way I read it he wants to use many of the classes in the CDM but just needs a few new attributes that apply to all classes. Jason On Sat, Jul 23, 2011 at 10:39 AM, John Doe <hornetl...@yahoo.com> wrote: ** Let me explain how this will work, for those of you who have not gone through an upgrade. The reason best practice is to add a custom class (outside of BMC.CORE) and add your own attributes to that custom class, with custom field ID ranges is because when you upgrade it will only keep these additions made this way. That's why I stated "I'd recommend you do not add them to Base Element. Instead create your own custom Class and add those attributes to that class. Otherwise, your next upgrade will be a nightmare." When you upgrade (which is inevitable) the Common Data Model is constantly changed and adapted. They will completely restructure all of the classes in BMC.CORE. Therefore, if you add custom fields to Base Element the upgrades will "remove" them. I have been through several upgrades and personally witnessed this. Obviously, if you have hundreds of thousands of records in these attributes you are up a creek with out a paddle. Patches sometimes will remove custom fields too. I know the road you are wanting to go down seems easier right now. But it will be a "nightmare" in the future. I would also recommend reading the book about How to Create a CMDB from the ground up. I have been through that mistake also. Take care and obviously your environment and situations will dictate your decisions. Good luck. _____ From: Mahesh <mchand...@gmail.com> To: arslist@ARSLIST.ORG Sent: Friday, July 22, 2011 2:35 PM Subject: Re: Adding Custom Attributes to Base Element ** One of the best practice with regards to customization is having a custom field ID range. Also, whenever you extend the data model, BMC recommends usage of a custom namespace instead of BMC.CORE . Thanks Mahesh On Fri, Jul 22, 2011 at 1:58 PM, pritch <pri...@ptd.net> wrote: I've had the same experience as Victor noted. I've added them with no problem - did need to work them forward through the joins. The only thing I'll add is to watch Field ID's. If the field ID that is used (generated or otherwise) is also used in another form feeding the same join, the field ID of one of those items on the join can change. If that happens and you build workflow to process the field, it can have some type mismatch issues (ie one is an integer and the other a date field). At least that's what we've seen. ----- Original Message ----- From: "Victor Olufowobi" <vic...@klub.chip.pl> To: arslist@ARSLIST.ORG Sent: Friday, July 22, 2011 2:21:23 PM Subject: Re: Adding Custom Attributes to Base Element ** Since these attributes need to apply to all further subclasses I don't think creating a custom class is a good idea. I have added a few attributes myself to Base Element without any issues. The time needed for the attributes to propagate to all existing subclasses depends on your system and the number of subclasses you have. You still need to modify the AST forms for the new attributes to be available in the required classes. Victor. On Fri 22/07/11 18:11 , "Alejandro Canon" aca...@extensionsa.com sent: ** John, Thanks for your recommendation. That custom class you mention should be a subclass of Base Element (BE), right? I´m asking that because I don’t see how a custom subclass of Base Element can propagate attributes to all existing subclasses in CDM. I was thinking creating a custom namespace and adding attributes in BE but stored in custom namespace. Alejandro. De: Action Request System discussion list(ARSList) [mailto:arslist@ARSLIST.ORG] En nombre de John Doe Enviado el: Viernes, 22 de Julio de 2011 12:00 Para: arslist@ARSLIST.ORG Asunto: Re: Adding Custom Attributes to Base Element ** Alejandro, I'd recommend you do not add them to Base Element. Instead create your own custom Class and add those attributes to that class. Otherwise, your next upgrade will be a nightmare. From: Alejandro Canon To: arslist@ARSLIST.ORG Sent: Friday, July 22, 2011 10:57 AM Subject: Adding Custom Attributes to Base Element ** Listers, ARS 7.6.04 SP1 CMDB 7.6.04 ITSM 7.6.04 I need to add about ten (10) attributes (common to all kind of CIs) to BaseElement. I’ve read some threads (dated about 2009) recommending to NOT ADD attributes in Base Element Class, because of known errors in Asset – CMDB Sync process. What’s your experience about that? Understanding CDM Model is based in CIM Model I think there shouldn’t be problems in adding fields to Base Element class. Believe me if I’m telling you I’ve reviewed all BaseElement attributes from BMC.CORE and BMC.AM namespaces and I have no match for these 10 attributes required. I guess a known issue could be extense time you may have to wait after saving changes in CDM, because custom attributes in Base Element must be propagated to all subclasses. Regards, Alejandro _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _______________________________________________________________________________ UNSUBSCRIBE or access ARSlist Archives at www.arslist.org attend wwrug11 www.wwrug.com ARSList: "Where the Answers Are" _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _attend WWRUG11 www.wwrug.com ARSlist: "Where the Answers Are"_ _______________________________________________________________________________ UNSUBSCRIBE or access ARSlist Archives at www.arslist.org attend wwrug11 www.wwrug.com ARSList: "Where the Answers Are"
