Work Group Service
History
Root access to all machines in order to perform customizations and system control (M. Böge, H. Grote and C. Iselin)
Customized shell setup in order to provide certain environment settings like default printers, default compiler switches, default path settings etc.
A customized HP VUE based desktop with the the HP VUE file manager `vuefile'
A network file system (NFS) which allowed access to user data physically located on one machine from all other machines
A central NIS user registry
Central installation of programs which were used by a large fraction of the group like MAD. At that time the anonymous account "slath" was used for this purpose
The /usr/local tree was provided by the central ASIS service
"Batch service" on a "good will" basis using proper nice values for long running processes
A WWW service based on the CERN http daemon (Home URL: http://hpariel.cern.ch/) for group related information and documentation
Boot support for X terminals owned by the group
Font service for the X terminals
Easy access to certain hardware components like cdrom drives, magneto optical drives and tape drives
The actual service consists of 2 HP D-Class SMP Servers with 2 160 Mhz PA-8000 64-bit processors with 512 Mb physical memory and 8Gb disk space. The machines involved are SLAP01 and SLAP02. A third machine has been ordered recently which will operate as a batch server where the other machines are for interactive use ONLY. The dispatcher SLAP.WGS.CERN.CH alias SLAP forwards users to the least loaded machine.
SLAPWGS
) reflects somehow the customization which was done for the old HP service ( ). In the following a comparison of the old ( ) and the new service ( ) is performed :
Root access to all machines in order to perform customizations and system control
On SLAPWGS only selected people from the IT division have root access (Tim Smith, Tony Cass). Members of the local group "slapstaff" (slapstaff::82:fci,hansg,ghislain,boege,jsberg) are allowed to
execute the script `killsi' invoked using `sudo' in order to kill processes of users belonging to the group "si". All customizations are done on the Group and Cluster level of the HEPiX environment. This reduces the amount of system administration work to a minimum and provides a homogenous machine setup
Customized shell setup in order to provide certain environment settings like default printers, default compiler switches, default path settings etc.
The Group level setup (see (5) in figure 1) foreseen in the HEPiX environment provides the members of the "si" group with a customized environment on all HEPiX conform nodes. The Cluster level setup (see (4) in figure 1) allows a customized setup of the Work Group Service SLAPWGS (See Group level setup and Cluster level setup)
A customized HP VUE based desktop with the the HP VUE file manager `vuefile'
SLAPWGS confronts the user with a similarly customized `fvwm' based desktop. The default File Manager is `moxfm' (See Desktop setup)
A network file system which allows access to user data physically located on one machine from all other machines
On SLAPWGS the standard network file system is AFS. All user data reside on central AFS volume servers (See AFS related information). The only exception is the /scratch/si area which is meant for storage of temporary data. The NFS file system of the old HP service is available for a short transition period (See NFS related information)
A central NIS user registry
On SLAPWGS central CERN user registration is performed via `(x)userreg'. User passwords are AFS passwords. Owing to the fact that the old HP service is still alive an automatic user registration procedure has been developed. Newly registered users on SLAPWGS get their account on the old HP service about one hour after their SLAPWGS registration
Central installation of programs used by a large fraction of the group like MAD
All group specific data are kept with respect to the HEPiX supported "si" group directory /afs/cern.ch/group/si (See Group directory structure)
The /usr/local tree
On SLAPWGS the /usr/local tree is provided by the central ASIS service. To gain performance some of the frequently
invoked packages are kept locally with respect to /asis.local (for example the emacs package)
Batch service
There is no "batch service" on a "good will" basis on SLAPWGS. Long running processes are reniced and finally killed by the WGSMON service. It is possible to launch batch jobs on CERNSP and SHIFT54 remotely from SLAPWGS (See Batch service)
WWW service for group related information and documentation
SLAP01 runs a WWW service on port 80 (Home URL: http://wwwslap.cern.ch/). The service is based on the APACHE http daemon (See WWW service)
Boot support for X terminals owned by the group
SLAP01 and SLAP02 provide a boot service for HP and NCD X terminals via TFTP (See X terminal support)
Font service for the X terminals
SLAP01 runs the font server `fs'on port 7100 (See Font service)
Easy access to certain hardware components like CDROM drives, magneto optical drives and tape drives
On SLAPWGS it mainly concerns the access to a magneto optical drive which is physically connected to a machine named HPSLAP03 which is the surviving of the old 3 HP9000/730/735 servers (See Hardware access)
Problems? The nice Micro Guide for HP Work Stations in the SL/AP Group by H. Grote and C. Iselin is still available (-> postscript version)
Have a look at:
this document ;-) (-> postscript version)
the introduction "UNIXhelp for Users". You can search the document if you have specific problems
the small collection of links on this WWW server
the CERN UNIX User Guide
John's collection of UNIX links
what the DESY people provide (USG Documentation)
MB
group_sys.conf.sh and group_sys.conf.csh:
These startup scripts for Bourne (.sh) and C (.csh) shells define some important environment variables for all shells (interactive and noninteractive):
group_login.sh and group_login.csh:
These startup scripts for Bourne (.sh) and C (.csh) define things to be done in login shells:
sys.conf.sh and sys.conf.csh:
These startup scripts for Bourne (.sh) and C (.csh) shells define some important environment variables for all shells (interactive and noninteractive):
env.sh and env.csh:
These startup scripts for Bourne (.sh) and C (.csh) shells define some important environment variables for all shells (interactive and noninteractive):
login.sh and login.csh:
These startup scripts for Bourne (.sh) and C (.csh) define things to be done in login shells:
zshrc and tcshrc:
xdm/Xresources:
xprofile:
xclients:
xclients.m:
The "feable" window manager `fvwm'
The file manager `moxfm'
To get used to the AFS terminology refer to the CERN AFS User's Guide and the AFS Disk Space Administration guide
To speed up AFS performance by increasing the cache cycle time on SLAPWGS the AFS cache size was set to 200000 1K byte blocks instead of 82365 1K byte blocks on CERNSP
There are three group related AFS protection groups under the control of the anonymous user "slath":
The concept of having a ~/public and ~/private directory has been extended to the ~/group directory which gives all AP group members read access to files with respect to this directory. All group members should create ~/group and give the correct permissions using the command `allow_slap ~/group'. Furthermore members are encouraged to create lep and lhc directories with respect to ~/group !
Locking the screen using the SL/AP session manager `session' leads to AFS token refresh ! Locking and unlocking the screen within less than 25 hours which is the expiration time of the token guaranties a valid token !
The user data of the old HP service can be found with respect to /nfs/ followed by the node name. Up to now seven nodes survived: hpanne, hplear, hpslap01, hpiago, hppuck, hpslap03, romeo
Recently a 10 processor Alpha Server (node name: SHIFT54) was acquired which has NFS based home directories. These home directories can be accessed from SLAPWGS via /u/si/ followed by the username. The scratch space /scratch on SHIFT54 can be accessed via /nfs/shift54/scratch (See figure 2)
Owing to the fact that "si" covers more or less the entire SL division the AP group information is not kept with respect to the HEPiX "si" Group home /afs/cern.ch/group/si but with respect to $AP_GROUP_DIR which is /afs/cern.ch/group/si/slap (see Group level setup)
The directory structure with respect to $AP_GROUP_DIR looks as follows:
bin Binaries doc Documents etc WWW service and HEPiX stuff home Links to members of the protection group slath:slap include Include files info Emacs info pages lib Platform dependent data, libraries man Manual pages project Pointers to group related projects scripts Platform independent scripts share Platform independent data src Source files tmp Temporary files
The old "slath" account is still available but reserved for the LEP optics database under ~slath/machines
LoadLeveler service
NQS++ service
To get an overview have a look at the SLAP WWW Service page
The binaries and configuration files are located with respect to the "ServerRoot" directory $AP_WWW_HOME_DIR. On SLAP01 this location is also reachable via /usr/local/etc/httpd
The "DocumentRoot" is $AP_WWW_HOME_DIR/htdocs which corresponds to the Home URL http://wwwslap.cern.ch/.
The server process (-> status) is controlled with the script `HTTPd start|stop' invoked using `sudo'. The members of the group "slapstaff" (slapstaff::82:fci,hansg,ghislain,boege,jsberg) are allowed to take this action
In order to help people to migrate to the new service a "fake" server has been introduced on HPSLAP03 redirecting people from http://hpariel.cern.ch/ to http://wwwslap.cern.ch/
A couple of scripts is periodically invoked under the user "boege" on SLAP01 in order to do some statistics on the server load and to retrieve publication lists from the preprints server (See $AP_WWW_HOME_DIR/cron/crontab.slap01 for details)
The directory $AP_WWW_HOME_DIR/Incoming which is local to SLAP01 contains temporary data like web counter files and
the SL/AP calendar database
The Apache URL Rewriting Module is used to fake an "xwho" service on this server (the "xwho" service is used on the SL page AP Group). New group members have to be added to the file $AP_WWW_HOME_DIR/htdocs/who/people/.htaccess !
To learn more about the server configuration refer to the Apache documentation and the Apache URL Rewriting Module document
The Harvest Broker software with Glimpse as indexing interface is running on SLAP01 on port 8500 and 8501 (-> Server Summary). The broker provides searchable information about web pages which are available via wwwslap.cern.ch. Specific search keys make it possible to restrict the search (examples are the MAD8 and SIXTRACK documents)
The binaries and configuration files are located with respect to the "HARVEST_HOME" directory $AP_HARVEST_HOME. On SLAP01 this location is also reachable via /usr/local/etc/harvest
broker, glimpseserver and gatherd are running under the anonymous user "harvest" (See ~harvest/cron/crontab.slap01 for details). The "gatherer" database is updated every week. Queries to the database can be performed using the form http://wwwslap.cern.ch/search/
The server software and the configuration files are located with respect to /usr/tftpdir
All X terminals should have "SLAP01" and "SLAP02" as primary and secondary boot servers with boot method "TFTP" selected. There is no support for anonymous NFS (See X terminal guide for details)
Most of the old HP9000/710 machines have been reconfigured as X terminals. They run the simple chooser script xtrc from /etc/inittab. There is also support for an X based chooser (Get chooser-HPUX.tar)
The configuration file config is located with respect to $AP_GROUP_DIR/lib/X11/fs
The fonts reside relativ to the fonts directory $AP_GROUP_DIR/lib/X11/fonts
The font server is running under the anonymous user "harvest" on SLAP01 (See ~harvest/cron/crontab.slap01 for details)
Magneto optical disk
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