NSTX MDSplus Server Update <19-Nov-2008>
Summary
The transition to serving NSTX MDSplus data from a Linux platform, skylark, occurred 19Nov2008.
MDSplus Data will no longer be served directly by servers on the VMS cluster. The VMS cluster will continue to provide (client) access to the data, via the Linux servers skylark and lark.
One will be able to connect to any tree via skylark or lark or VMS. For these systems, trees that are actually served by a remote machine are accessible to you, but performance will be degraded as compared to an MdsConnect to the machine that directly serves the tree.
Trees currently served by VMS (europa, birch, kees, luna), which will soon be served by skylark: nstx, activespec, activesp_raw, cameras, derived, ed, edge, eng_trend, engineering, eng_dev, efitrt, efitrt_dev, fueling, gaspuffimgng, mptscalib, nstx_trend, operations, particles, passivespec, pspec_raw, rf, wf.
Trees currently served by lark : larknstx, befit, befit**, cameras2, dcon, efit, efit??, efitanalysis, efitanalys**, lrdfit, lrdfit**, microwav_raw, microwave, mmwr, mse, nbi, ops_pc, probes, profdb, pspec_pc, sflip, ucla_interf, usxr .
the lark computer (Linux) will remain in operation, as-is, for the time being. It is planned to integrate its operations into a skylark cluster during the LLD-pause planned for summer 2009.
Cluster and Desktop Environment Changes
If you access MDSplus data from the VMS or a unix cluster, the modules and other standard environment settings will be changed by the Computer Division.
If you access MDSplus data from a 'desktop' computer, you may want to reconfigure your registry/environment to point to skylark instead of a VMS machine (e.g. europa) in order to realize better performance:
If you access MDSPlus from a 'test cell' diagnostic PC, using LabVIEW: You should edit your LabVIEW program to MDSconnect to skylark instead of europa/kees/luna. It is recommended that mdsplus events be sent to skylark, but can also be sent to birch (VMS).
Known Issues & work-around
1) On VMS, you cannot use some TCL commands. VMS' version is old and doesn't forward the mdstcl commands to a remote server. However, you can use the 'mdstcl' function in IDL. Linux hosts do forward mdstcl requests to the remote server.
2) The VMS mdir 'alias' does not work on VMS. Bill Davis made a work-around.
3) To EDIT a tree, you must be logged on to the computer that hosts the server for that tree. This is no different than before, just pointing out this behavior. Most tree-owners have accounts on the MDSplus servers.
Additional Material (a bit outdated)
Contact list:
Bill Davis 609-243-2546 bdavis@pppl.gov
Paul Sichta 609-243-3477 psichta@pppl.gov
Greg Tchilinguirian 609-243-2669 gtchilin@pppl.gov
Gretchen Zimmer 609-243-3133 gzimmer@pppl.gov