So, in your considered opinion, would it be wiser to go with one cell, put up with potential quorum snafus, ensure the clients set their preferred server to a local one, and move R/W volumes when users move locations? Or to go with multiple cells, perhaps one as master, and resolving ambiguities on a per-volume basis depending on how that volume is intended to be used?
> -----Original Message----- > From: [email protected] > Sent: Mon, 19 Jan 2009 19:02:59 -0500 > To: [email protected] > Subject: Re: [OpenAFS] AFS design question: implementing AFS over a > highly-distributed, low-bandwidth network > > Chaz Chandler wrote: >>>> 2) There is no good AFS-based solution for group shares in this >>>> scenario. >>> i don't agree with that, but it depends on your interpretation. >> >> Ah, good. What would you recommend? > > The problem you are facing is that OpenAFS does not support read-write > replication. There can only be one instance of a read-write volume at a > time. If your model is > >>>> Further questions: >> >>>> a) What is the best way to replicate a volume across cells? > > There isn't a defined mechanism for this and doing so can create some > problems specific to the attempt to do so. As far as each OpenAFS cell > is concerned the volumes are not replicas. If modifications are made in > multiple cell instances they will diverge. It is possible to use one > cell as a master and from that cell dump volume images that can then be > pushed into other cells. However, they should be treated as readonly in > the alternate cells. > >>>> b) How would the presence of multiple cells effect the krb5 >>>> infrastructure (currently: one realm, one cell, cell name = realm name >>>> = >>>> internal LAN domain name)? >>> it doesn't have to be. you can have many cells in a realm, for >>> instance, the sipb.mit.edu, athena.mit.edu, etc cells in the >>> ATHENA.MIT.EDU realm. >> >> True, but is it as simple as adding an afs/newc...@realm principle and >> making sure the >> users get tokens for all cells? > > Yes. On Windows the Network Identity Manager provider and/or the > OpenAFS integrated logon network provider will permit you to automate > this for your users. > >>>> c) Are any of the Morgan Stanley volume management system utilities >>>> available publicly, or are their methods sufficiently documented >>>> publicly? All of what I've read about them are from previous >>>> afsbpw's. >>>> (ie, >>>> http://workshop.openafs.org/afsbpw08/talks/wed_1/OpenAFS_and_the_Dawn_of_a_New_E >> ra.pdf) >>> as far as i know none of their tools are distributed at this time. >> >> Anyone know any Morgan Stanley folks with whom I could chat about this >> stuff? Is this >> something others would be interested in as well? > > In my opinion, the Morgan Stanley tools are not general purpose. They > do what they do but are very specific to the way that Morgan Stanley > built their infrastructure. > > Jeffrey Altman ____________________________________________________________ FREE 3D MARINE AQUARIUM SCREENSAVER - Watch dolphins, sharks & orcas on your desktop! Check it out at http://www.inbox.com/marineaquarium _______________________________________________ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
