"Learn the intricacies of the AIX file system framework. Every operating system provides a native kernel framework that kernel developers have to understand and adhere to when developing a piece of a kernel component for that operating system. This article sheds some light on the AIX file system framework. You need to understand the framework in order to develop a new file system, or to port an existing file system to the AIX operating system."
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Member since:2007-06-01
I'm not familiar with the history of the volume managers. But from this link: http://www-03.ibm.com/servers/aix/products/aixos/whitepapers/lvm_ve...
I assume IBM developed the LVM by them self. Not 100% sure at all. The IBM FS (JFS2) is developed by IBM.
http://en.wikipedia.org/wiki/IBM_Journaled_File_System_2_(JFS2)
Thought the IBM JFS2 and HP-UX JFS are totaly different.
Member since:2006-01-19
I'm not familiar with the history of the volume managers. But from this link: http://www-03.ibm.com/servers/aix/products/aixos/whitepapers/lvm_ve.....
I assume IBM developed the LVM by them self. Not 100% sure at all. The IBM FS (JFS2) is developed by IBM.
Well, I have seen those 'translation' docs for HP-UX LVM versus VxVM too, so I don't know if that shows much. What I did find that is interesting is this old thread:
http://www.osnews.com/comment.php?news_id=13874&limit=no&threshold=...
In which one of the posters presents a somewhat convincing argument that the LVM in OSF was from IBM. Of course this is around 1990 and so printed sources are going to be the problem. At any rate, I do believe IBM has licensed Veritas IP, regardless of what the LVM looks like. But I am much more sure that this is the case with Tru64 (and of course HP-UX) than with AIX.
The IBM FS (JFS2) is developed by IBM.
http://en.wikipedia.org/wiki/IBM_Journaled_File_System_2_(JFS2)
Thought the IBM JFS2 and HP-UX JFS are totaly different.
Agree 100%. What I am not totally clear on is how close Linux JFS is to IBM JFS2.
Member since:
2006-01-19
In HP-UX online FS resizing is a feature that costs extra?!?! What server OS is one that can't resize a stupid FS online? Mirroring the vg00? That costs extra too
I guess this is the downside of HP OEMing Veritas VM and FS. So far as I know, this attaches a fixed license fee to every CPU you license for HP-UX, and of course features cost extra to keep Veritas (Symantec) happy. I wonder if the free Veritas SF release helped HP to negotiate the free LVM features increase?
Not that I am saying that I think integrating the Veritas code was a bad idea--actually, I think it was a reasonable move and made a lot of sense in a time when open source was not especially on the radar. But I am pretty sure that Solaris is the only UNIX which was free enough of third party licensed code to be open sourced reasonably, and perhaps 'staying independent' was the better strategy.
On the AIX side, I am under the impression that the original volume management code came from OSF through Veritas and is thus also encumbered and requires a fixed fee to Veritas for every CPU (I think this was also the case with Tru64). Is this so?