Saturday, November 14, 2009

CentOS 5.x Samba Domain Controller With LDAP Backend

This will show you how to set up a Samba Domain Controller with a local LDAP backend, using CentOS 5.x (tested on 5.3, still successfully running on 5.4).

Includes a web-interface for managing LDAP users/groups/etc.

Disable selinux:
It will only cause problems, I'm not going to mess with SELinux in this guide other than disabling it.

# echo 0 >/selinux/enforce

Within /etc/sysconfig/selinux, set:

Install some tools
rpm -Uvh

# yum update
# yum install openldap-servers nss_ldap samba httpd openssl mod_ssl mysql mysql-server php php-xml php-ldap php-mysql php-pdo php-cli php-common smbldap-tools

Installing smbldap-tools this way should install all the dependent perl modules, however the version available on yum has some bugs, so we'll upgrade to the latest version afterwards, keeping the dependencies, but overwriting the smbldap-tools package:

# rpm -Uvh

Set up the hostname
For our purposes in this guide, we are calling the server's hostname "dc1" and the domain "DOMAINNAME".

Note: If you want to use your fqdn for your Samba domain, wherever you see ,dc=DOMAINNAME below, replace it with ,dc=example,dc=com, assuming your fqdn is

Also note that "root" will be the samba administrator username, if you don't like that, change it as well. Related lines are: cn=root and cn: root

Within /etc/hosts, add or replace your line (following the file's format, assuming is your server's network-accessible IP): dc1.DOMAINNAME dc1

Set your hostname on the command line:

hostname dc1.DOMAINNAME

Generate a master password and set up ldap

# slappasswd

Note the output of slappasswd, you will insert it into slapd.conf in a minute.

# mv -f /etc/openldap/slapd.conf /etc/openldap/slapd.conf.dist

Click here to find out more!
Insert the following text into /etc/openldap/slapd.conf:
include /etc/openldap/schema/core.schema
include /etc/openldap/schema/cosine.schema
include /etc/openldap/schema/inetorgperson.schema
include /etc/openldap/schema/nis.schema
include /etc/openldap/schema/samba.schema

allow bind_v2
pidfile /var/run/openldap/
argsfile /var/run/openldap/slapd.args

database bdb
suffix "dc=DOMAINNAME"
rootdn "cn=root,dc=DOMAINNAME"
rootpw {SSHA}TTzshhAbmZPPb8F2s7sgf9B+IrZt+nUD
password-hash {SSHA}
directory /var/lib/ldap

index cn,sn,uid,displayName pres,sub,eq
index uidNumber,gidNumber eq
index sambaSID eq
index sambaPrimaryGroupSID eq
index sambaDomainName eq
index objectClass pres,eq
index default sub

Note the rootpw line in the above text, that's where you paste your output from slappasswd.

# cp /usr/share/doc/samba-3.*/LDAP/samba.schema /etc/openldap/schema/
# cp /etc/openldap/DB_CONFIG.example /var/lib/ldap/DB_CONFIG
# chown ldap:ldap /var/lib/ldap/DB_CONFIG
# chmod 600 /var/lib/ldap/DB_CONFIG

Insert the following text into /etc/openldap/init.ldif:
objectclass: dcObject
objectclass: organization
o: CentOS Directory Server
dn: cn=root,dc=DOMAINNAME
objectclass: organizationalRole
cn: root

# slapadd -l /etc/openldap/init.ldif
# chown -R ldap:ldap /var/lib/ldap
# chmod 600 /var/lib/ldap/*
# slapcat

slapcat should produce something very similar to the following output:
objectClass: dcObject
objectClass: organization
o: CentOS Directory Server
structuralObjectClass: organization
entryUUID: 717d1b1e-ce90-102d-88c3-df22563ebfee
creatorsName: cn=root,dc=DOMAINNAME
modifiersName: cn=root,dc=DOMAINNAME
createTimestamp: 20090506134920Z
modifyTimestamp: 20090506134920Z
entryCSN: 20090506134920Z#000000#00#000000
dn: cn=root,dc=DOMAINNAME
objectClass: organizationalRole
cn: root
structuralObjectClass: organizationalRole
entryUUID: 71858556-ce90-102d-88c4-df22563ebfee
creatorsName: cn=root,dc=DOMAINNAME
modifiersName: cn=root,dc=DOMAINNAME
createTimestamp: 20090506134920Z
modifyTimestamp: 20090506134920Z
entryCSN: 20090506134920Z#000001#00#000000

# service ldap start
# chkconfig ldap on
# ldapsearch -x -b "dc=DOMAINNAME"

The output from ldapsearch should be very similar to the following:
# extended LDIF
# LDAPv3
# base  with scope subtree
# filter: (objectclass=*)
# requesting: ALL
objectClass: dcObject
objectClass: organization
o: CentOS Directory Server
dn: cn=root,dc=DOMAINNAME
objectClass: organizationalRole
cn: root
# search result
search: 2
result: 0 Success
# numResponses: 3
# numEntries: 2
Setting up remote administration of the ldap directory
Edit /etc/php.ini and make sure memory_limit is set to at least 32 MB:
memory_limit = 32M
Last I checked, the version of phpldapadmin available via yum is broken, so we'll get the latest & extract it: Go To & download the latest version. In my case that resulted in the following commands, your package may be newer:
# mkdir /var/www/html/samba && cd /var/www/html/samba
# wget
# tar zxf phpldapadmin-
# ln -s phpldapadmin- pla # cp pla/config/config.php.example pla/config/config.php
Now edit ./pla/config/config.php and uncommment the following line:
$config->custom->jpeg['tmpdir'] = "/tmp";
Make newly setup software available
# service httpd restart # chkconfig httpd on
Edit /etc/sysconfig/iptables and copy & modify line about ssh (--dport 22 -j ACCEPT), and right after it, add (assuming your CentOS install produced the default iptables file):
#Allow Https://
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 443 -j ACCEPT
#Allow samba:
-A RH-Firewall-1-INPUT -m multiport -p udp --dport 137,138 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m multiport -p tcp --dport 139,445 -j ACCEPT
Now open your webbrowser and visit and login with Username cn=root,dc=DOMAINNAME & your password. You should be able to look around and see some junk. Integrate ldap and Samba
# mv /etc/samba/smb.conf /etc/samba/smb.conf.dist # cp /usr/share/doc/smbldap-tools-0.9.5/smb.conf /etc/samba/smb.conf
Edit /etc/samba/smb.conf to your likings, the default ldap part should be fine.
# cp /usr/share/doc/smbldap-tools-0.9.5/smbldap.conf /etc/smbldap-tools/smbldap.conf # net getlocalsid
Note, net getlocalsid will error a bunch until the end, because you haven't fully configured samba yet -- but will produce the sid you need for the next step. Edit /etc/smbldap-tools/smbldap.conf and insert sid, domain, etc, all throughout the file till the end. Edit /etc/smbldap-tools/smbldap_bind.conf and change both applicable lines, change "secret" to your password.
# chmod 644 /etc/smbldap-tools/smbldap.conf # chmod 600 /etc/smbldap-tools/smbldap_bind.conf # authconfig-tui
Check that the output from authconfig-tui contains:
[ ] Local authorization is sufficient
Now test your samba config:
# testparm
# smbpasswd -w YOUR_ROOT_LDAP_PASS_HERE # smbldap-populate
# smbldap-populate will ask for the password, enter it. Start the LDAP Samba installation up
# /etc/init.d/smb start # chkconfig smb on
Add users/groups, correlate between unix and ldap:
# useradd user1 # smbldap-useradd -a -G 'Domain Users' -m -s /bin/bash -d /home/user2 -F "" -P user1
Get a picture of the UNIX groups that aren't there yet that LDAP assumes:
# net groupmap list
Output is something like:
Domain Admins (S-1-5-21-990788473-1556064292-4137819756-512) -> domain_admins
Domain Users (S-1-5-21-990788473-1556064292-4137819756-513) -> domain_users
Domain Guests (S-1-5-21-990788473-1556064292-4137819756-514) -> 514
Domain Computers (S-1-5-21-990788473-1556064292-4137819756-515) -> 515
Administrators (S-1-5-32-544) -> 544
Account Operators (S-1-5-32-548) -> 548
Print Operators (S-1-5-32-550) -> 550
Backup Operators (S-1-5-32-551) -> 551
Replicators (S-1-5-32-552) -> 552
Add correlating groups to unix, using the suggested GIDs:
# groupadd -g 514 samba_domain_guests # groupadd -g 515 samba_domain_computers # groupadd -g 544 samba_administrator # groupadd -g 548 samba_account_operators # groupadd -g 550 samba_print_operators # groupadd -g 551 samba_backup_operators # groupadd -g 552 samba_replicators
If you want to add a non-built-in group to LDAP/Samba, say forcontrolling which users can write/read files on a share, and have it
determine that by groups:
# smbldap-groupadd -a "People In Our Office"
Then get the output from net groupmap list again and correlate the newly created group # just like last time, adding the group to the unix system:
# groupadd -g 1001 samba_people_in_our_office
Add users to LDAP groups via the web interface, then correlate in unix:
Also add computer accounts to unix, using the group
"samba_domain_computers" from above, and where your allowed computer
names end with a "$":
# useradd -M -g 515 -s /bin/false officecomp1$
Edit /etc/samba/smb.conf and make sure under global, nt acl support = yes Last, but certainly not neccessary, you may want to turn off the unneccesary services CentOS runs by default. I determined that I, specifically, don't need any of the following. You might be different, so look them up before you turn them off:
# chkconfig ntpd off # chkconfig bluetooth off # chkconfig xinetd off # chkconfig smartd off
# chkconfig yum-updatesd off # chkconfig rpcidmapd off # chkconfig rpcgssd off # chkconfig restorecond off # chkconfig portmap off # chkconfig pcscd off # chkconfig nfslock off # chkconfig mcstrans off # chkconfig mdmonitor off # chkconfig irqbalance off # chkconfig kudzu off # chkconfig ip6tables off # chkconfig hidd off # chkconfig gpm off # chkconfig haldaemon off # chkconfig autofs off # chkconfig avahi-daemon off # service ntpd stop # service bluetooth stop # service xinetd stop # service smartd stop # service yum-updatesd stop # service rpcidmapd stop # service rpcgssd stop # service restorecond stop # service portmap stop # service pcscd stop # service nfslock stop # service mcstrans stop # service mdmonitor stop # service irqbalance stop # service kudzu stop # service ip6tables stop # service hidd stop # service gpm stop # service haldaemon stop # service autofs stop # service avahi-daemon stop

1 comment:

  1. Dear Sir,

    Can you post the documents how to 389+samba+dovecot+ftp(for Centos 5.4).

    J Mahto