Debugging hints

Here are some useful things to check and mention when contacting us for help:

Check the version of the gLExec version:

/opt/glite/sbin/glexec -v

Check the file permissions of the gLExec executable.

For all run-modes of gLExec, the gLExec must be executable for all users.

• For running gLExec in setuid mode, preferably use one of the following modes (setuid and setgid):

glexec: mode: 6111, 6511, 6711; owned by root:glexec
glexec.conf: mode: 0440; owned by root:glexec

• In case setgid is not possible, preferably use one of the following modes (only setuid):

glexec: mode: 4111, 4511, 4711; owned by root:glexec or root:root
glexec.conf: mode: 0444; owned by root:glexec or root:root

• For running gLExec in logging only mode, preferably use one of the following modes:

glexec: mode: 0111, 0511, 0711; owned by root:glexec or root:root
glexec.conf: mode: 0444; owned by root:glexec or root:root

Before continuing with testing: The gLExec Exit Codes and the Environment variables

The following pages might hold interesting to glance through before proceeding with your debugging:

• Proxy file handling in gLExec: All the details about the environment variables used by gLExec.
• Exit codes of gLExec: All the details about the exit codes of gLExec.

Test the exit codes by printing them on the shell by showing the value of $? Example:

/opt/glite/sbin/glexec /usr/bin/id -a; echo $?

Execute with exported GLEXEC_CLIENT_CERT and exported X509_USER_PROXY, with the full path

See Proxy file handling in gLExec for the purpose of these environment variables.

export GLEXEC_CLIENT_CERT=`pwd`/mkproxy-x509-voms
export X509_USER_PROXY=`pwd`/mkproxy-x509-voms

Is the user account that tries to use gLExec whitelisted?

Method 1.: the calling account is a member of the 'glexec' primary or secondary group.

Method 2.: the account or the pool is whitelisted in the glexec.conf. See the Man pages of gLExec for more details on the whitelist options.

Note: when gLExec fails with a 'user not whitelisted' error, this might be caused by an unreadable glexec.conf file: in case the glexec.conf file is unreadable, gLExec uses its buildin defaults, including whitelisting only unix accounts which are member of the glexec group.

Example test script for gLExec

Testing basic functionality:

#!/bin/sh

TESTPROXY=/tmp/x509up_`id -u`

export GLEXEC_CLIENT_CERT=$TESTPROXY
export X509_USER_PROXY=$TESTPROXY

/opt/glite/sbin/glexec /usr/bin/id -a ; echo $?

Testing with the transfer of a specific proxy file:

#!/bin/sh

TESTPROXY=/tmp/x509up_`id -u`

export GLEXEC_CLIENT_CERT=$TESTPROXY
export X509_USER_PROXY=$TESTPROXY
export GLEXEC_SOURCE_PROXY=$TESTPROXY

/opt/glite/sbin/glexec /usr/bin/id -a ; echo $?

Testing multi-user Pilot Job scenarios:

#!/bin/sh

VOMSINFO=`which voms-proxy-info`

PILOT_PROXY=/tmp/x509up_`id -u`
TARGET_USER_PROXY=`pwd`/other.proxy 

export X509_USER_PROXY=$PILOT_PROXY
export GLEXEC_CLIENT_CERT=$TARGET_USER_PROXY
export GLEXEC_SOURCE_PROXY=$TARGET_USER_PROXY

$VOMSINFO -all
/opt/glite/sbin/glexec $VOMSINFO -all