IBM RS/6000 SP, Problem Determination Manual

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3.7.5 dsh and p* Commands
The
dsh
command uses rsh to execute a specific AIX command on any group of
nodes or other remote RS/6000 hosts within the authentication realm, in parallel.
The group of target hosts may be pointed to by the WCOLL variable, which in
turn points to a file containing the hostname of each target host.
There are various
p*
commands (
p_cat, pcp, pdf, pfck
), which all use dsh to
execute a specific AIX command in parallel on multiple hosts.
3.7.6 rsh and rcp
There is a Kerberos-authenticated version of both
rsh
and
rcp
in the
/usr/lpp/ssp/rcmd/bin directory. To use the Kerberos versions, the user must
include this directory before the /usr/bin directory in the local host
′
s PATH.
If the user
′
s authentication fails, the
/usr/lpp/ssp/rcmd/rsh
(or
rcp
) command
issues an error message and passes its arguments to
/usr/bin/rsh
(or
rcp
). In
this case the user will require normal remote command access to the remote
host (through /etc/hosts.equiv or $HOME/.rhosts).
3.7.7 sysctl
The
sysctl
command provides a command line interface for communicating with
the sysctl remote command execution and monitoring server, sysctld. Sysctl
connects to a remote host
′
s sysctld using TCP/IP, passes keywords and
commands to the server, and writes output returned to stdout. Any sysctl user
must be a Kerberos principal.
3.8 Solving Problems
There are a few basic things to check when Kerberos authentication fails. The
following hints and tips should be followed before taking the more drastic
measure of rebuilding the entire Kerberos database. Also consult Chapter 6,
“Diagnosing Authentication Problems,” in the
RS/6000 Scalable POWERparallel
Systems: Diagnosis and Messages Guide, GC23-3899 for further information.
3.8.1 Daemons
Start by checking that both the kerberos and the kadmind daemons are running.
If the daemons are not running, then check /etc/inittab. The entries for these
two daemons should be similar to the following:
root@sp21cw0 /etc > lsitab kerb
kerb:2:respawn:/usr/lpp/ssp/kerberos/etc/kerberos
root@sp21cw0 /etc > lsitab kadm
kadm:2:respawn:/usr/lpp/ssp/kerberos/etc/kadmind -n
Figure 34. inittab Entries for Kerberos Daemons
If the /etc/inittab file is correct, then try to start the daemons from the command
line. Also check the Kerberos daemon log files in the /var/adm/SPlogs/kerberos
directory for any error messages, which may explain why the daemons cannot
be respawned.
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SP PD Guide