Linux IOC Operations at NSTX - An Overview P. Sichta 28Mar2005

References EPICS website ( – Applications Developer Guide. –Training documents. –Tech-Talk mailing list. NSTX Documents –VxWorks IOC NSTX-WBS6-OP-009, EPICS IOC Reboot NSTX-WBS6-OP-005, EPICS IOC Shutdown NSTX-WBS6-OP-015, Configuring IOC Boot Parameters NSTX-WBS6-DV-003, Preparing an MVME-177 for vxWorks –Linux IOC NSTX-WBS6-DV-015, Building EPICS Base, Extensions, and a softIOC on Linux for a Linux target. NSTX-WBS6-OP-027, EPICS Linux IOC Operations. NSTX-WBS6-??-???, Managing a Linux IOC. Plan to restructure ‘Linux’ IOC documents.

Introduction This presentation describes how to operate the IOC, not how to: –build it, –configure it, –get databases onto it, –get sequence programs onto it, –troubleshoot problems.

vxWorks and Linux IOCs - Introduction A Linux IOC offers a much lower-cost and higher-performance solution for an EPICS control system. A Linux IOC is not a real-time system, so its Application should be reviewed in this light. The CI&C operator’s user interface with the Linux IOC is quite different from the vxWorks IOC.

what is epics? Getting Started with EPICS: Introductory Session I Pioneering Science and Technology Office of Science U.S. Department of Energy Power Supply Beam Position Monitor Vacuum Gauge Computer Interface Process Variables: Channel Access Server S1A:H1:CurrentAO S1:P1:x S1:P1:y S1:G1:vacuum iocCore Channel Access Client

EPICS Configuration at NSTX Windows Linux Solaris vxWorks KEY NSTX Firewall Engineering Physics/PPPL x-term OPI vxWorks IOCs epicsrv1 CA clients nstxpc09 (LV Web Server) epicsgate02 EPICS Gateway CAR-2, Archive Data Server epicsrv2 nstxIOC1 (Linux IOC) no OPERATIONS role, only vxWorks support epicsrv4 epicsrv3 Linux IOCs x86 OPI CA clients

VxWorks and Linux IOCs CategorySome things are the sameSome things are different Network & CA clients From the network and CA client point of view, a Linux IOC and a vxWorks IOC look the same. That is, they both use the Channel Access protocol over TCP/IP. No differences! Database A ‘database’ file can run on either type of IOC... same flat-file, ASCII format. Some records call device support and driver support that are specifically written for vxWorks and VME modules. Many records in EPICS Base can use soft Device support, which works with both OS’s. Sequencer Programs A ‘sequencer program’ can run on either type of IOC... same source syntax (SNL in an.st file). Existing SNL programs may need to be rewritten in an OSI-compliant manner. Subroutines A ‘subroutine’ can run on either type of IOC... same source syntax (C file). Existing subroutines may need to be rewritten in an OSI-compliant manner.

vxWorks and Linux IOCs - The Physical vxWorksLinux

vxWorks and Linux IOCs - The iocCore Software Tasks vxWorks Linux

vxWorks and Linux IOCs - a ‘Terminal’ Session LOCAL REMOTE vxWorksLinux RS-232 connection to Console port. MACse running VersaTerm. PC running HyperTerm. Maybe no local Console, otherwise local VGA/kybd.. (Probably) no Linux graphical interface (text only). Use the Screen utility to access the IOC Shell. rlogin protocol to vxWorks using tornado user account. One remote user at a time. Use logout command to terminate session. SSH to Linux, using xxx user account. Use the Screen utility to access the IOC Shell. Use ‘Ctrl-A D’ command to terminate (IOC shell) session.

vxWorks and Linux IOCs - Booting & Starting iocCore vxWorksLinux Power up VME Crate or RESET the CPU. Use ‘boot’ vxWorks script, e.g: <st.boot_ioc1 Power up Linux PC or reboot the CPU. Use ‘boot’ Linux script, e.g.: boot_ioc

vxWorks and Linux IOCs - Status Check vxWorksLinux MEDM displays Alarm Handler Terminal sessions MEDM displays Alarm Handler Terminal sessions

vxWorks and Linux IOCs - Shutdown vxWorksLinux No graceful IOC shutdown needed at this time, but once I/O is present it may be required. Probably run a ‘shutdown’ script, then the normal exit command. Linux needs an orderly shutdown. This vxWorks scripts gracefully terminates communications tasks, and shuts down the IOC.

The First ONLINE Linux IOC at NSTX

NSTX’s First Linux IOC It is on the NSTX Physics (.15) network. –The computer’s name is nstxioc1.pppl.gov. It’s purpose is to foster secure integration between ‘Engineering ops’ and ‘Physics ops’. It is presently an orphaned Dell L667 desktop machine, but will be something else in FY06. Integrated into MEDM and Alarm Handler. –It sees the Engineering IOC’s via the EPICS Gateway –Engineering IOC’s see it directly Use a reverse gateway?

Looking deeper, it’s a prototype The computer’s name is nstxioc1.pppl.gov. The IOC’s medm and ALH name is ‘IOCs1’. The ioc’s Linux process/task is ‘lin7’. The ioc home directory is /eprun/epicApps/ioc157/iocBoot/ioclin7 The IOC’s operator account is epics. The computer is presently in Sichta’s office, but will move into the NSTX Control Room. The database was made using VDCT on Sichta’s office PC. Database hand-transferred to nstxioc1 using sftp, using the freeware WinSCP. In the near future, this needs to change (somehow) to provide a reasonable way of ‘doing business’.

Linux IOC Status via MEDM

Linux IOC in the Alarm Handler

What does it do? Monitors LabVIEW Web Server (nstxpc09). –ALH monitors these records to alarm if Web Server VI crashes. Will soon receive EPICS Events for NSTX Clock Events (sourced by IOC1). Would like to use it to field NSTX Clock Control commands from Ben LeBlanc: –his computer’s hole through the NSTX firewall can be closed – his epicsrv account can be disabled Would like to use it to receive ca_puts from critical NSTX VMS and unix tasks: – indicate that they are running, ready, etc... –DAS CAMAC Link and crate status –status these items on MEDM displays (e.g. COE display) –Integrate items into the Alarm Handler

vxWorks and Linux IOCs - Summary The CI&C operator’s user interface with the Linux IOC is quite different from the vxWorks IOC. Future work that will affect IOC Operations: –CyberSecurity –improved IOC Shell access? –remote boot and management –device and driver support for I/O

To figure out... how to: –name it. –build it. –configure it. –get databases onto it. –get sequence programs onto it. –manage code for vxWorks and Linux targets. –troubleshoot problems.