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A.2. Troubleshooting sudo with SSSD and sudo Debugging Logs

A.2.1. SSSD and sudo Debug Logging

The debug logging feature enables you to log additional information about SSSD and sudo.

The sudo Debug Log File

To enable sudo debugging:
  1. Add the following lines to /etc/sudo.conf: 
    Debug sudo /var/log/sudo_debug.log all@debug
Debug sudoers.so /var/log/sudo_debug.log all@debug
  2. Run the sudo command as the user you want to debug.
The /var/log/sudo_debug.log file is created automatically and provides detailed information to answer questions like:
  • What information is available about the user and the environment when running the sudo command? 
    sudo[22259] settings: debug_flags=all@debug
sudo[22259] settings: run_shell=true
sudo[22259] settings: progname=sudo
sudo[22259] settings: network_addrs=192.0.2.1/255.255.255.0 fe80::250:56ff:feb9:7d6/ffff:ffff:ffff:ffff::
sudo[22259] user_info: user=user_name
sudo[22259] user_info: pid=22259
sudo[22259] user_info: ppid=22172
sudo[22259] user_info: pgid=22259
sudo[22259] user_info: tcpgid=22259
sudo[22259] user_info: sid=22172
sudo[22259] user_info: uid=10000
sudo[22259] user_info: euid=0
sudo[22259] user_info: gid=554801393
sudo[22259] user_info: egid=554801393
sudo[22259] user_info: groups=498,6004,6005,7001,106501,554800513,554801107,554801108,554801393,554801503,554802131,554802244,554807670
sudo[22259] user_info: cwd=/
sudo[22259] user_info: tty=/dev/pts/1
sudo[22259] user_info: host=client
sudo[22259] user_info: lines=31
sudo[22259] user_info: cols=237
  • What data sources are used to fetch sudo rules? 
    sudo[22259] <- sudo_parseln @ ./fileops.c:178 := sudoers: files sss
  • SSSD plug-in starts with this line: 
    sudo[22259] <- sudo_sss_open @ ./sssd.c:305 := 0
  • How many rules did SSSD return? 
    sudo[22259] Received 3 rule(s)
  • Does a rule match or not? 
    sudo[22259] sssd/ldap sudoHost 'ALL' ... MATCH!
sudo[22259] <- user_in_group @ ./pwutil.c:1010 := false

The SSSD Debug Log Files

To enable SSSD debugging:
  1. Add the debug_level option to the [sudo] and [domain/domain_name] sections of your /etc/sssd/sssd.conf file: 
    [domain/domain_name]
debug_level = 0x3ff0
...
[sudo]
debug_level = 0x3ff0
  2. Restart SSSD: 
    # systemctl restart sssd
  3. Run the sudo command to write the debug information to the log files.
The following log files are created:
The domain log file: /var/log/sssd/sssd_domain_name.log
This log file helps you to answer questions like:
  • How many rules did SSSD return? 
    [sdap_sudo_refresh_load_done] (0x0400): Received 4-rules rules
  • What sudo rules did SSSD download from the server? 
    [sssd[be[LDAP.PB]]] [sysdb_save_sudorule] (0x0400): Adding sudo rule demo-name
  • Are the matching rules stored in the cache? 
    [sdap_sudo_refresh_load_done] (0x0400): Sudoers is successfully stored in cache
  • What filter was used to download the rules from the server? 
    [sdap_get_generic_ext_step] (0x0400): calling ldap_search_ext with [(&(objectClass=sudoRole)(|(!(sudoHost=*))(sudoHost=ALL)(sudoHost=client.example.com)(sudoHost=client)(sudoHost=192.0.2.1)(sudoHost=192.0.2.0/24)(sudoHost=2620:52:0:224e:21a:4aff:fe23:1394)(sudoHost=2620:52:0:224e::/64)(sudoHost=fe80::21a:4aff:fe23:1394)(sudoHost=fe80::/64)(sudoHost=+*)(|(sudoHost=*\\*)(sudoHost=*?*)(sudoHost=*\2A*)(sudoHost=*[*]*))))][dc=example,dc=com]
    Use this filter to look up the rules in the IdM database: 
    # ldapsearch -x -D "cn=Directory Manager" -W -H ldap://server.example.com -b dc=example,dc=com '(&(objectClass=sudoRole)...)'
The sudo responder log file: /var/log/sssd/sssd_sudo.log
This log file helps you to answer questions like:
  • How many rules did SSSD return? 
    [sssd[sudo]] [sudosrv_get_sudorules_from_cache] (0x0400): Returning 4-rules rules for [user@idm.example.com]
  • What filter was applied for searching the cache of SSSD? 
    [sudosrv_get_sudorules_query_cache] (0x0200): Searching sysdb with [(&(objectClass=sudoRule)(|(sudoUser=ALL)(sudoUser=user)(sudoUser=#10001)(sudoUser=%group-1)(sudoUser=%user)(sudoUser=+*)))]
  • How do I look up the rules returned from the SSSD cache? Use the following filter to look up the rules: 
    # ldbsearch -H /var/lib/sss/db/cache_domain_name.ldb -b cn=sysdb '(&(objectClass=sudoRule)...)'

    Note

    The ldbsearch utility is included in the ldb-tools package.