User:Tom/RHCE EX300-2

25 Configuring Kerberos

KDC     Key Distribution Center. A central key server. Issues tickets.
Realm   All hosts taht use the same KDC to get tickets.
TGT     Ticket Granting Ticket

Principal name nfs/server.example.com@EXAMPLE.COM
User name      tom@EXAMPLE.COM

Using nslcd or sssd as Authentication Backend Service

Verify that sssd packges are installed before using the authconfig utilities.. Use a gui, sssd is then used by default. Use yum group install "Directory Client" to install sssd and related packages. Start sssd before using the authconfig utilities.

/etc/sysconfig/authconfig
FORCELEGACY=no                Switch off nslcd.
USESSSD=yes
USESSSDAUTH=yes

Commands

authconfig                Configure LDAP authentication with Kerberos authorization.
authconfig --test         Get an overview of the current configuration and see what services are used.
authconfig-tui
authconfig-gtk

kinit                      Obtain and cache kerberos ticket-granting ticket.
klist                      Lists cached Kerberos tickets.

Files

/etc/krb5.keytab             Needed by a server hosting Kerberized services. Contains names of all service principals on that server.

/etc/nslcd.conf              Alternative for sssd.
/etc/nsswitch.conf 
/etc/openldap/cacerts        Stores root certificate authorities
/etc/openldap/ldap.conf      LDAP client configuration
/etc/pamd.d/
/etc/sssd/sssd.conf          Daemon used for retrieving and caching user and authentication information.
                             Install sssd service before using the authcong utilities (yum install group "Directory Client").
/etc/sysconfig/authconfig    

Packages

pam_krb5
krb5-workstation

26 iSCSI

Commands

targetcli
firewall-cmd --add-service iscsi-target --permanent
firewall-cmd --reload
systemctl start target
systemctl enable target

iscsiadm

Packages

targetcli

...

34 DNS

Unbound is the preferred package.

Install, enable and start unbound.

/etc/unbound/unbound.conf

35 MariaDB

install mariadb mariadb-server mariadb test
systemctl start mariadb
systemctl enable mariadb

Italic text

firewall-cmd --add-service mysql --permanent

mysql_secure_installation
/usr/libexec/mysqld --help --verbose          Information about all the settings

show databases;
use databases;
create database dbname;
create tsble tablename (name varchar(40),place varchar(40));
describe tablename;

delete from tablename where field = ' value ';
update tablename set field = value where field2 = ' value ';
insert into tablename (field1,field2) values(' value1 ',' value2 ');

where clause = <> > >= <  >= BETWEEN LIKE IN

create user username@'localhost' identified by password;
drop user 'username'@'localhost';
grant select,update,delete,insert on *.* to username@'localhost';  
grant all priviliges on ...

mysqldump -u root =p -p database --databases >dumpfileItalic text
drop database databasename;
create database databasename;
mysql -u root -p -p databasename <dumpfile;

37 Samba

man mount.cifs credentials= option

39 Configure SSH

semanage port, man sshd_config, ssh-agent, ssh-add, ssh tunnel.

40 Time synchronisation

Chronyd daemon, chronyc command. ntp port 123. start, enable, firewall-cmd --add-service

List commands
getsebool -a                      List all selinux booleans
seinfo                            SELinux policy query tool
         --all
         -r                       List all roles
         -t                       List all types (*-t)
         -u                       List all users
semanage boolean --list           List SELinux booleans with comments
semanage fcontext -l              List all current rules