Automatically restart Puppet

Previously, I wrote about how puppet v2 had memory leaks so I had to have Nagios restart puppet. (http://legendofgou.blogspot.com/2013/10/puppet-has-memory-leaks.html)

Well, I finally upgraded to puppet v3 a few months ago and the same plugin doesn't seem to work anymore. Below is the updated Nagios plugin to restart the puppet agent. I'm not saying v3 has memory problems but why not have it monitor and restart dead agents or agents that may be having issues?

#!/usr/bin/perl
# Author: Gou Yang
# Purpose: Checks and restarts puppet if the memory is too high
#          or if puppet is dead

use strict;

my $default;
my $pcount;
my @Results;
my $memResults;

my $logResults;

#puppet seems to hang randomly
#so, if puppet hasn't logged to messages then it should be restarted
$logResults=`sudo /usr/bin/tail -400 /var/log/messages | grep puppet-agent | grep Finished | wc -l`;
if ($logResults < 1) {
  `sudo /etc/init.d/puppet restart`;
  print "WARNING - puppet-agent isn't reporting, restarting puppet";
  exit 1;
}

$default=10;
chomp($pcount=`ps aux | grep "/usr/bin/ruby /usr/bin/puppet agent" | grep -v grep | wc -l`);

if ($pcount < 2) {
 if ($pcount < 1) {
  print "WARNING - No Puppet Process found, restarting puppet";
  `sudo /etc/init.d/puppet restart`;
  exit 1;
  }
   @Results=split(" ",`ps aux | grep "/usr/bin/ruby /usr/bin/puppet agent" | grep -v grep`);
   $memResults=$Results[3];
    if ($memResults > $default) {
    `sudo /etc/init.d/puppet restart`;
    print "WARNING - Memory utilization of $memResults\% is too high, restarting puppet";
    exit 1;
    }
  else{
    print "OK - Memory utilization is $memResults\%";
    exit 0;
  }
}
else{
  print "WARNING - Found $pcount puppet processes";
  exit 1;
}

How to custom install Splunk Forwarder using Puppet - Part 2

This is a continuation from "How to custom install Splunk Forwarder". I recently had to handle special inputs.conf for special servers. So, I had to separate out the inputs.conf file. In the below example, I named the source file "inputs-web.conf" and "puppet-serial-web.txt" to differentiate the original files from these files.

I added these two sections in to their own spunk::forweb class and removed the original two sections from the original splunk class. I then, simply "include splunk" and "include splunk::forweb" in my nodes declaration and I'm all set.

So, in the future, if I had a need for a special inputs.conf for say, a database machine, I can create a new splunk::fordb class and "include splunk" and "include splunk::fordb" in the node declaration for the database machine.

Example:

    file { "/opt/custom/splunk/splunkforwarder/etc/apps/search/local/inputs.conf":
      ensure  => present,
      source  => "puppet:///modules/splunk/splunk-files/inputs-web.conf",
      group   => "splunk",
      owner   => "splunk",
      mode    => "644",
      require => File["/opt/custom/splunk/splunkforwarder/etc/apps/search/local"],
    }
    file { "/opt/custom/splunk/splunkforwarder/.puppet-serial.txt":
      ensure  => present,
      source  => "puppet:///modules/splunk/splunk-files/puppet-serial-web.txt",
      group   => "splunk",
      owner   => "splunk",
      mode    => "644",
      require => File["/etc/pki/tls/private/cert4splunk.p12"],
    }

How to use phpldapadmin to configure OpenLDAP 2.4

This is assuming you currently use phpldapadmin to admin your OpenLDAP server. If you're not, you should think about it. phpldapadmin is super easy to setup and use.

In your phpldapadmin config file, scroll down to the bottom where it says "If you want to configure additional LDAP servers..." and uncomment that section. Change the name value to 'Config' and change the host value to '$yourhost'. Also add 'cn=config' (assuming, thats what you set your config to, otherwise, set it to match your config) to the base value. See Example below.

Modify other variables as you see fit.

Once you got everything completed, log on to your phpldapadmin URL. You should now see a drop down that says 'Server Select'. Select your 'Config' server and log in. Enjoy.

<snip>
/**************************************************************************
 * If you want to configure additional LDAP servers, do so below.         *
 * Remove the commented lines and use this section as a template for all  *
 * your other LDAP servers.                                               *
 **************************************************************************/

$servers->newServer('ldap_pla');
$servers->setValue('server','name','Config');
$servers->setValue('server','host','127.0.0.1');
$servers->setValue('server','port',389);
$servers->setValue('server','base',array('cn=config'));
 </snip>

Here is a screen shot. As you can see, you can now easily edit anything and simply click 'update object'. If you need to import or export, that can also be easily accomplished with the 'import' and 'export' links. No need to run any fancy ldap command line. 

How to setup ppolicy in OpenLDAP 2.4

STEP ONE - Prepare the environment

I'm running CentOS 6.5 and OpenLDAP 2.4.23

Make sure ppolicy schema exists and add it to cn=schema if it does not
Make sure your modulepath is pointing to the path where your ppolicy.la exists
Example: /usr/lib64/openldap


You're also going to have to add an overlay for ppolicy. Here is an LDIF I exported using my test instance. You can use it if you like.

# LDIF Export for olcOverlay={0}ppolicy,olcDatabase={1}bdb,cn=config
# Server: Config (127.0.0.1)
# Search Scope: base
# Search Filter: (objectClass=*)
# Total Entries: 1
#
# Generated by phpLDAPadmin (http://phpldapadmin.sourceforge.net) on February 22, 2014 3:47 pm
# Version: 1.2.3

version: 1

# Entry 1: olcOverlay={0}ppolicy,olcDatabase={1}bdb,cn=config
dn: olcOverlay={0}ppolicy,olcDatabase={1}bdb,cn=config
objectclass: olcOverlayConfig
objectclass: olcPPolicyConfig
olcoverlay: {0}ppolicy
olcppolicydefault: cn=default,ou=ppolicy,dc=test,dc=com
olcppolicyforwardupdates: FALSE
olcppolicyhashcleartext: TRUE
olcppolicyuselockout: TRUE

STEP TWO - Install the password check module
Next step is to install a password checker module, if you want to use a password checker module. It's easy to say no, but I recommend that you do. Anyway, you can get the source from their repository at:
http://tools.ltb-project.org/projects/ltb/files

This was the only password checker module I found when I was googling for one and it seems to work quite well.

Once you extract everything, you will want to edit the Makefile. Set the path to your openldap header files. You probably don't have it installed. If you do, great. If you don't, you can either install the source RPM or you can grab the source from openldap here:
http://www.openldap.org/devel/gitweb.cgi?p=openldap.git;a=summary

On this web page, just find the openldap version you need and click on it. Since I am running OpenLDAP v2.4, I clicked on OPENLDAP_REL_ENG_2_4.

On the next page, I clicked on the snapshot link for "Update dates for release  OPENLDAP_REL_ENG_2_3_23" since I am running v2.4.23

After you've extracted the source code, you need to execute "./configure" followed by "make depend"
That's it. You're done with the OpenLDAP package.

Back to the password checker. Now, I set LDAP_INC in the make file to the location where I extracted openldap source as follows:


LDAP_INC=-I/home/user/openldap-src/include \
         -I/home/user/openldap-src/servers/slapd

That's it. Now, you are ready to compile the module. See what the output is supposed to look like below. By the way, I got an error the first time I ran make. It was because crack/cracklib was not installed. I ran 'yum install cracklib-devel cracklib crack' and that resolved it.

ltb-project-openldap-ppolicy-check-password-1.1 $ make
rm -f check_password.o check_password.so check_password.lo
rm -f -r .libs
gcc -g -O2 -Wall -fpic -DHAVE_CRACKLIB -DCRACKLIB_DICTPATH="\"/usr/share/cracklib/pw_dict\"" -DCONFIG_FILE="\"/etc/openldap/check_password.conf\"" -DDEBUG -c -I/home/user/openldap-src/include -I/home/user/openldap-src/servers/slapd  check_password.c
gcc -shared -o check_password.so check_password.o -lcrack
ltb-project-openldap-ppolicy-check-password-1.1 $ 

You now should have a check_password.o and check_password.so file. Copy or move these two files in to your module path. In my case, I copied them in to  /usr/lib64/openldap.

STEP THREE - Configure your server
Restart your openldap server.

Import the below in to your openldap server. The values I have are for testing purposes. You will need to modify it for your use.

dn: cn=users,ou=ppolicy,dc=company,dc=com
cn: users
objectclass: top
objectclass: device
objectclass: pwdPolicy
objectclass: pwdPolicyChecker
pwdallowuserchange: TRUE
pwdattribute: userPassword
pwdcheckmodule: check_password.so
pwdcheckquality: 2
pwdexpirewarning: 0
pwdfailurecountinterval: 0
pwdgraceauthnlimit: 0
pwdinhistory: 2
pwdlockout: TRUE
pwdlockoutduration: 600
pwdmaxage: 0
pwdmaxfailure: 4
pwdminage: 30
pwdminlength: 8
pwdmustchange: TRUE
pwdsafemodify: FALSE

Edit your ldap.conf and insert or modify the following:

pam_password clear

pam_lookup_policy yes

Note: You need to NOT hash the password on the machine in order to allow openldap to be able to read the password. That way, the password history will be honored. If you set "pam_password md5" or anything other than clear, password history will not be honored. Don't worry about security though, just make sure you are using TLS. Also, don't worry about openldap storing the password in the clear because by default it doesn't. It should store it in SSHA like below. I took this screen shot using phpldapadmin "show internal attributes".

Create the configuration file for password checker at /etc/openldap/check_password.conf

The content of the conf file is fully explained at the LTB site:

http://ltb-project.org/wiki/documentation/openldap-ppolicy-check-password

How to configure centos 6 for ldap auth using puppet

I looked at some of the ldap modules for puppet on github. It looks complicated. I'm not really sure why it has to be so complicated.

Alright, so here is the easy way to do it. I'm using Puppet v2.x but it's the same concept for any configuration manager.

Enable LDAP Auth
On your centos 6 test client, run the authconfig command. I've provided a simple example below. Make sure you pass --help to authconfig so you can see all of the options. Your options will likely be different from mine.

example:
authconfig --update  --ldapserver=myldapserver.domain.com --ldapbasedn=dc=sub,dc=domain,dc=com --enablesssd --enablesssdauth --enablelocauthorize --enablemkhome

Make sure authentication works the way you expect it to work.

Replicate the working configs
Copy the following files to your puppet master:
/etc/openldap/ldap.conf
/etc/nsswitch.conf
/etc/pam.d/system-auth-ac
/etc/pam.d/password-auth-ac
/etc/sssd/sssd.conf

Create a module to sync these files. After the sync, you have to restart sssd. I've included my sample module below. In my sample, I am running a mix of v5 and v6. Therefore, I am using a variable to determine the difference.

When a new machine is provisioned, puppet will sync the necessary files and restart sssd and authentication will work immediately. Once you get this going, it is pretty much, set it and forget about it. 

class auth {

  case $lsbmajdistrelease {
    '5': {
      file { "/etc/ldap.conf":
        ensure => present,
        source => "puppet:///modules/auth/cent5/ldap.conf",
        group  => "root",
        owner  => "root",
        mode   => "644"
        }
      file { "/etc/nsswitch.conf":
        ensure  => present,
        source  => "puppet:///modules/auth/cent5/nsswitch.conf",
        group   => "root",
        owner   => "root",
        mode    => "644",
        require => [ File["/etc/ldap.conf"], File["/etc/pam.d/system-auth-ac"] ],
        }
      file { "/etc/pam.d/system-auth-ac":
        ensure => present,
        source => "puppet:///modules/auth/cent5/system-auth-ac",
        group  => "root",
        owner  => "root",
        mode   => "644"
        }
    }#5

    '6': {
      file { "/etc/openldap/ldap.conf":
        ensure => present,
        source => "puppet:///modules/auth/cent6/ldap.conf",
        group  => "root",
        owner  => "root",
        mode   => "644"
        }
      file { "/etc/nsswitch.conf":
        ensure  => present,
        source  => "puppet:///modules/auth/cent6/nsswitch.conf",
        group   => "root",
        owner   => "root",
        mode    => "644",
        require => [ File["/etc/openldap/ldap.conf"], File["/etc/pam.d/system-auth-ac"], File["/etc/pam.d/password-auth-ac"], File["/etc/sssd/sssd.conf"] ],
        }
      file { "/etc/pam.d/system-auth-ac":
        ensure => present,
        source => "puppet:///modules/auth/cent6/system-auth-ac",
        group  => "root",
        owner  => "root",
        mode   => "644"
        }
      file { "/etc/pam.d/password-auth-ac":
        ensure => present,
        source => "puppet:///modules/auth/cent6/password-auth-ac",
        group  => "root",
        owner  => "root",
        mode   => "644"
        }
      file { "/etc/sssd/sssd.conf":
        ensure => present,
        source => "puppet:///modules/auth/cent6/sssd.conf",
        group  => "root",
        owner  => "root",
        mode   => "600"
        }
        #in v6, we have to restart sssd in order for the ldap changes to take affect
        exec { restart_sssd:
          command     => "/etc/init.d/sssd restart",
          refreshonly => true,
          subscribe   => File["/etc/openldap/ldap.conf",
                              "/etc/pam.d/system-auth-ac",
                              "/etc/pam.d/password-auth-ac",
                              "/etc/sssd/sssd.conf",
                              "/etc/nsswitch.conf"],
          require     => File["/etc/nsswitch.conf"],
        }

    }#6

  }#case
}#class