WP4 hands-on workshop: EDG LCFGng exercises

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WP4 hands-on workshopEDG LCFGng exercises

• German.Cancio_at_cern.ch

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Overview

• LCFGng Exercises
• Simple reconfiguration of root password
• Changing polling interval, forcing profile
  updates
• Managing users
• Managing RPMs
• Installing and managing components

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Exercise 1Simple client reconfigurationchangin
g the root password of the client
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Simple client reconfiguration (I)

• Proceed
• Log on to the server XXX.cern.ch (see blackboard)
• As root, password XXXX (see blackboard)
• Log on your client
• As root machine name and password on blackboard
• On the server, start editing your machines
  configuration file
• cd /var/obj/conf/server/source
• vi or emacs ltmymachinegt
• Change the clients root password
• Use an encrypted password generated eg. with
  perl
• perl e print crypt(mypassword,rt)
• Change auth.rootpwd to the new encrypted password

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Simple client reconfiguration (II)

• Compile the profile using mkxprof, verifying that
  no errors or warnings produced
• /usr/sbin/mkxprof v ltmynodegt use v s for
  updating web pg
• Wait until the profile is propagated to the
  client ( 60 seconds)
• The client node is notified automatically of
  changes using UDP, but sometimes UDP packages are
  lost, so there is also a regular polling.
• On the client, check that the configuration has
  been received
• Run qxprof qxprof auth.rootpwd
• On the client, check that /etc/shadow has been
  updated properly.
• Open another connection to the client, and verify
  that your new root password actually works -)
• On the client, check the auth log file in
  /var/obj/log/auth

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Exercise 2Changing client polling interval,
force profile updates
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LCFGng polling and profile updates (I)

• The client.poll resource defines the polling
  interval
• qxprof client.poll
• Poll5m1m -gt this means that a poll is done
  every 5 minutes plus a random interval ranging
  from zero seconds to 1m.
• To change the polling frequence, edit your client
  component configuration file, and add a line
• client.poll 1m1s
• This will set the polling to 1m and a random
  interval of 1s.
• Reminder the before client tells rdxprof
  to overwrite an existing value.
• Run mkxprof on the server
• Go to the client, wait for a moment and verify
  that the polling interval has been changed in the
  profile
• qxprof client.poll
• Poll1m1s

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LCFGng polling and profile updates (II)

• You can now run ps auxwwwwwgrep client and
  verify that the rdxprof process has now the new
  poll interval.
• LCFG profile updates can be forced by restarting
  the client by hand.
• /etc/obj/client restart will do this.
• This may be useful in case the client process
  hangs for whatever reason.

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Exercise 3Adding users
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Adding users (I)

• Users have to be defined in the auth.XXX
  resources.
• auth.users space separated list of user login
  names
• auth.userpwd_ltuserXgt, auth.userhome_ltuserXgt,
  auth.usergroup_ltuserXgt
• But, if we want to ADD a user to the already
  existing user list, we cant just redefine
  auth.users!
• If we define in a header file (animal-farm-users.h
  )
• auth.users napoleon squealer snowball
• And we want to add a user boxer in our
  machines config file
• include animal-farm-users.h
• auth.users boxer
• The end result will be only boxer! Since the
  old value is overwritten.
• The EXTRA macro defined in macros-cfg.h is useful
  here.
• include animal-farm-users.h
• EXTRA(auth.users) boxer
• The end result will be auth.users napoleon
  squealer snowball boxer

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Adding users (II)

• Exercise
• Edit your machines configuration file, include
  animal-farm-users.h, and add the following
  user
• Username Horse Boxer
• Login name boxer
• Encrypted password ltpick onegt
• Home directory /home/boxer
• Group farm
• Shell /bin/sh
• Hint have a look at how animal-farm-users.h
  defines users -)
• Hint2 use the EXTRA macro -)
• Compile the configuration with mkxprof
• On the client, verify that /etc/password and
  /etc/shadow have been regenerated, and that the
  home directory has been created.

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Adding users (III)

• Exercise (contd.)
• Removing users just remove all configuration
  entries related to the user (or remove
  appropriate include statements), and re-run
  mkxprof.
• Note that the home directories of removed users
  are not deleted.
• Homework Check the man page of the auth
  component (man edg-lcfg-auth) for more resources
  to configure.

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Exercise 4Adding and removing RPMs
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Adding and removing RPMs (I)

• In order to add/remove packages to a client, the
  corresponding RPMs have to be added to the
  Repository and to the RPM configuration files.
• Updaterpms requires to generate special RPM
  header files. These RPM header files are created
  and updated by running make in the repository
  area directories after downloading the RPMs.
• Have a look at the Makefile under
  /opt/local/linux/6.2/RPMS/LCFGng
• The RPM configuration files are stored under
  /opt/local/linux/6.2/rpmcfg
• The configuration file is defined by the
  component configuration resource
  updaterpms.rpmcfg
• Run on the client qxprof updaterpms.rpmcfg to
  find out your configuration file.

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Adding and removing RPMs (II)

• Adding a RPM to the Repository
• Copy the RPM to the repository location on the
  server, ie.
• cp myrpm-1.2-3.noarch.rpm /opt/local/linux/6.2/RPM
  S/WPx
• Generate the RPM header file by issuing
• cd /opt/local/linux/6.2/RPMS/WPx make
• The header file is named as the original RPM
  but starting with a .
• Dont forget to run make!
• Removing a RPM from the Repository
• cd /opt/local/linux/6.2/RPMS/WPx
• rm myrpm-1.2-3 .myrpm-1.2.3 remove both RPM
  and header

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Adding and removing RPMs (III)

• Adding an RPM to the configuration
• Include a line with a and the name of the
  RPM.
• The version and release can be specified, or set
  to - which means take the latest
  version-release of this package found on the
  server
• Example emacs-21.4-3 ? take the emacs 21.4
  release 3
• Example xeyes-- ? take the latest version of
  xeyes
• Removing RPMs from the configuration listed in a
  included template
• Use the - prefix instead of for removing an
  RPM even if it has been declared in a header
  file.
• Example -xeyes-- ? remove (any version of)
  xeyes

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Adding and removing RPMs (IV)

• Ignoring locally installed RPMs
• By default, updaterpms removes all RPMs which
  are not found in the RPM configuration file.
• However, it is possible to avoid erasing some
  RPMs by declaring them in the RPM configuration
  file
• xeyes--i ? keeps any version of xeyes you
  have on the node.
• It is also possible to set the updaterpms.localpkg
  s resource to yes.

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Adding and removing RPMs (V)

• By default, updaterpms is started by via cron at
  1 AM. It is not started automatically on config
  changes.
• Updaterpms can be also started by hand, by
  running the updaterpms component
• /etc/obj/updaterpms start
• Note that, if you use wildcards (-) in the RPM
  config, the wilcard expansion is done when you
  run updaterpms, and not when you run mkxprof!
• Documentation man page for updaterpms (man
  updaterpms), man page for the updaterpms
  component (man edg-lcfg-updaterpms)

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Adding and removing RPMs (VI)

• Exercise Add RPMs to the configuration of your
  node.
• Edit in /opt/local/linux/6.2/rpmcfg your RPM
  configuration file (hint use qxprof on the
  client to find out which one to edit)
• Add the following RPM package the latest version
  of the package called edg-lcfg-syslog.
• Start the updaterpms component. Verify that the
  package has been installed by running rpm q
  edg-lcfg-syslog.
• Remove the package from the node using
  rpm e edg-lcfg-syslog
• Run again updaterpms. The package should be
  installed again.
• Edit the RPM configuration file, and remove the
  line for edg-lcfg-syslog.
• Start the updaterpms component verify that
  edg-lcfg-syslog is removed.

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Exercise 5Adding, configuring, running
components
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Adding/configuring LCFGng components (I)

• LCFG components are packaged in two RPMs
• edg-lcfg-foo or lcfg-foo contains all necessary
  files for the client
• edg-lcfg-foo-defaults or lcfg-foo-defaults
  contains the server default configuration.
• The LCFGng server RPM can be installed with the
  rpm command on the server, while as the client
  RPM has to be installed with updaterpms on the
  client (see exercise 4).
• A component has to be also added to two component
  resources
• profile.components ? list of components
  used on the client
• boot.services ? list of components to start
  at boot time
• Each component requires also some specific
  configuration
• Pprofile.version_ltcomponentgt ? set to 1.
• ltcomponentXgt.resourceY (component specific
  resources).

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Adding/configuring LCFGng components (II)

• Exercise Add the syslog component to your
  client.
• Verifications
• Verify that edg-lcfg-syslog RPMs are available on
  the server (hint in the RPMS/LCFGng directory).
• Verify that the RPM header files are also
  there.
• Verify that the server RPM is installed on the
  server.
• Add to your RPM configuration file the latest
  version of edg-lcfg-syslog.
• On the client, run /etc/obj/updaterpms start. The
  RPM should be now installed
• Verify with rpm q on client.

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Adding/configuring LCFGng components (III)

• On the client, read the edg-lcfg-syslog man page.
  Look specially at the RESOURCES section.
• (On the server), edit your component
  configuration file, and
• add the necessary entries for profile.components,
  boot.services (use the EXTRA macro)
• define profile.version_syslog to 1.
• Set the kern. messages to go to
  /var/log/kernel.log (see the man page above!)
• Run mkxprof. Verify on the client (with qxprof)
  that the resources are OK.
• On the client, start the syslog component with
  /etc/obj/syslog start
• From now on, the component is reconfigured
  automatically.
• Look at the /etc/syslog.conf file. Is the kern.
  entry there?
• Remove the kern. entry in the component
  configuration file. Run mkxprof, and verify that
  the kern. entry has been removed from
  /etc/syslog.conf on the client.

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Adding/configuring LCFGng components (IV)

• The same principle described here applies to all
  components.
• Most components are included by default in the
  EDG RPM and component configuration files.
• However, they may require site-specific
  configurations.