Linux Automation. Thomas Cameron. Red Hat. Colorado Software Summit: October 19 24, Copyright 2008, Copyright holder.

Transcription

1 Linux Automation Thomas Cameron Red Hat Slide 1

2 Welcome! Thanks for taking the time to attend this presentation! I want this to be very interactive, questions are encouraged! This deck is available with a bunch of extra hidden slides on automation with RHN Satellite/Spacewalk at Slide 2

3 Agenda Automating your Linux installation with kickstart system-config-kickstart RHN Satellite/Spacewalk (hidden) anaconda-ks.cfg Slide 3

4 Agenda Using kickstart for bare metal Using boot.iso Using vmlinuz and initrd.img Using DHCP and PXE Required packages Setting up DHCP (/etc/dhcpd.conf file) Setting up PXE Ensuring appropriate services are running Slide 4

5 Agenda Kickstarting virtual machines From the command line Graphically using virt-manager Slide 5

6 Agenda Provisioning Amazon Elastic Compute Cloud systems Time permitting, a demonstration Slide 6

7 Automating with Kickstart The kickstart file (typically ks.cfg) contains the answers to the questions asked by the installer Minimizes human error/inconsistency Reduces time to production Slide 7

8 Automating with Kickstart Sections of the kickstart file Basic configuration Installation method Boot loader options Partition information Network configuration Authentication Firewall configuration Display configuration Slide 8

9 Automating with Kickstart Basic Sections of the kickstart file Package selection Pre-installation script Post-installation script Slide 9

10 system-config-kickstart Be aware that this utility will use installation information gathered from your system's repositories Only root can query those repositories so this must be run as root (I know, I know...) Slide 10

11 Basic Configuration Language Keyboard Time Zone and UTC (use UTC!) Root password Installation Number Architecture Reboot after install Text or Graphical Interactive Mode (bad idea) Slide 11

12 Basic Configuration Slide 12

13 Installation Method New or Upgrade Install Method CD-ROM NFS FTP (includes login options) HTTP Hard Drive (FAST!) Slide 13

14 Installation Method Slide 14

15 Boot Loader Options Install or not GRUB password MBR or first section of boot partition (good for dual boot with Windows) Extra kernel parameters (e.g. noapic or irqpoll) Slide 15

16 Boot Loader Options Slide 16

17 Partition Information Clear MBR (good idea) Remove all, Linux or no partitions If removing, initialize (clear) disk label Note that this tool does not do LVM yet! Slide 17

18 Partition Information Slide 18

19 Network Configuration Mostly for DHCP or static addresses Slide 19

20 Network Configuration Slide 20

21 Authentication Use shadow passwords (strongly recommended) Use MD5 passwords (strongly recommended) NIS Slide 21

22 Authentication LDAP Kerberos Hesiod SMB (Windows authentication) Name Switch Cache Daemon (nscd) Slide 22

23 Authentication Slide 23

24 Firewall Configuration On or off (strongly recommend on) SELinux (strongly recommend Active, come back for my SELinux for Mere Mortals presentation) Trusted devices (e.g. internal interface on a multi-homed system) Trusted services (pretty basic list) Other ports (port:protocol, comma separated) Slide 24

25 Firewall Configuration Slide 25

26 Display Configuration On or off (I usually do not install X on servers, if you don't then leave this off) Color depth and resolution Default desktop Start X on boot Firstboot on, off or reconfigure Video card (recommend probe) Monitor (recommend probe) Slide 26

27 Display Configuration Slide 27

28 Package Selection Be aware that s-c-k gathers this information using root privileges! This installer is not as smart as the one used during installation you can't right-click on a choice and choose all At minimum, choose Base System/Base Slide 28

29 Package Selection Slide 29

30 Pre-Installation Very infrequently used This script runs before DNS is enabled, so networking is active but you must use ip addresses Runs while installation partitions still mounted on /mnt/sysimage Slide 30

31 Pre-Installation Slide 31

32 Post-Installation Very frequently used After installation, /mnt/sysimage is remounted (chrooted) to / Post scripts can run before or after that chroot Slide 32

33 Post-Installation Slide 33

34 Saving the ks.cfg File/Save File Review and edit as needed Best to copy, not move to web site, nfs export or wherever (to inherit correct SELinux context) Slide 34

35 Saving the ks.cfg Slide 35

36 Sample ks.cfg #platform=x86, AMD64, or Intel EM64T # System authorization information auth --useshadow --enablemd5 # System bootloader configuration bootloader --location=mbr # Partition clearing information clearpart --none # Use text mode install text # Firewall configuration firewall --enabled --http --ssh --port=443:tcp,8080:tcp,tcp:tcp # Run the Setup Agent on first boot firstboot --disable key 49af89414d # System keyboard keyboard us Slide 36

37 Sample ks.cfg # System language lang en_us # Installation logging level logging --level=info # Use network installation url --url= # Network information network --bootproto=dhcp --device=eth0 --onboot=on # Reboot after installation reboot #Root password rootpw --iscrypted $1$AZCiptqF$Dp2Jw0lkz8rgxYJQY7wk81 # SELinux configuration selinux --enforcing Slide 37

38 Sample ks.cfg # System timezone timezone --isutc America/Chicago # Install OS instead of upgrade install # X Window System configuration information xconfig --defaultdesktop=gnome --depth=24 --resolution=1280x1024 -startxonboot # Disk partitioning information part /boot --bytes-per-inode= fstype="ext3" --size=100 part swap --bytes-per-inode= fstype="swap" --size=520 part / --bytes-per-inode= fstype="ext3" --grow --size=1 %post # install Sun Java rpm -Uvh --nodeps Slide 38

39 Sample ks.cfg # Set up PATH and JAVA_HOME environment variables perl -pi.old1 -e 's/export PATH/PATH=\"\/usr\/java\/default\/bin\/:\ $PATH\"\nJAVA_HOME=\"\/usr\/java\/default\"\nexport PATH/' /etc/profile perl -pi.old2 -e 's/export PATH USER LOGNAME MAIL HOSTNAME HISTSIZE INPUTRC/export PATH USER LOGNAME MAIL HOSTNAME HISTSIZE INPUTRC JAVA_HOME/' /etc/profile # Create JBoss user useradd -u 8080 jboss echo redhat passwd --stdin jboss # Install JBoss AS su - jboss -c "wget su - jboss -c "unzip -qq jboss ga-jdk6.zip" Slide 39

40 Sample ks.cfg # Turn off ip version 6 echo install ipv6 /bin/true >> /etc/modprobe.conf Slide 40

41 Making media available Via web server Via NFS Via ftp Slide 41

42 Via web server First method: mount the ISO loopback under /var/www/html Don't forget to mount it with the right SELinux context (see my SELinux for Mere Mortals presentation also here at CSS) Saves disk space only the space used by the ISO is used Slide 42

43 Via the web server Slide 43

44 Via the web server Slide 44

45 Via web server Copy (to inherit SELinux context) the ks.cfg into /var/www/html Slide 45

46 Via the web server Slide 46

47 Via the web server Slide 47

48 Via web server Second method: Copy the contents of the ISO to a directory under /var/www/html Use cp -r (not -a or -p) so the files will inherit the context of the /var/www/html directory Slide 48

49 Via the web server Slide 49

50 Via NFS Copy the ISO image to a directory and export it via NFS Copy ks.cfg to exported directory The installing machine will see it and mount it loopback Slide 50

51 Via NFS Slide 51

52 Via ftp Copy contents of ISO to a directory under /var/ftp/pub, as with http Slide 52

53 RHN Satellite/Spacewalk Red Hat Network Satellite Server (RHNS) Lifecycle management tool for RHEL Commercially supported/subscription based Slide 53

54 RHN Satellite/Spacewalk Upstream project is Spacewalk (SW): For any RPM based distro No cost, Open Source Slide 54

55 RHN Satellite/Spacewalk This presentation will only cover general kickstart features of Satellite/Spacewalk Slide 55

56 Kickstart on RHNS/SW Log in and choose Systems/Kickstart/Profiles/create new kickstart profile Slide 56

57 Kickstart on RHNS/SW Slide 57

58 Creating the kickstart Define the kickstart label Choose the base channel (distro) Choose the tree (update level) Choose virtualization type Para-virtualized host - installing on bare metal with virtualization services Para-virtualized guest - installing virtual machine in RHEL virtualization environment None - installing on bare metal with no virtualization services Slide 58

59 Creating the kickstart Slide 59

60 Creating the kickstart Note the installation location This is where the installation media is available Satellite/Spacewalk to not actually share static installation trees, the packages are dynamically made available via dynamically generated trees. This saves tons of space on the server Alternatively you can point to an existing install location Slide 60

61 Creating the kickstart Slide 61

62 Creating the kickstart Enter the root password for the new system Slide 62

63 Creating the kickstart Slide 63

64 Creating the kickstart Now you can customize the installation For instance, log all post-install scripts via Kickstart Details/Details: Slide 64

65 Creating the kickstart Slide 65

66 Creating the kickstart Under Kickstart Details/Operating System, choose appropriate child channels At minimum RHN Tools Channel In this example, clustering and clusterstorage: Slide 66

67 Creating the kickstart Slide 67

68 Creating the kickstart Under Kickstart Details/Advanced Options, set installation method, install or upgrade, network settings, language, installation number, partitioning, time zone, SELinux, password, video settings, X configuration, iscsi, etc. Slide 68

69 Creating the kickstart Slide 69

70 Creating the kickstart Under System Details/Details, set reinstallation networking, SELinux, enable RHN configuration management and enable remote commands and set root password Slide 70

71 Creating the kickstart Slide 71

72 Creating the kickstart Under System Details/Locale, set time zone and set the clock to use UTC if appropriate Slide 72

73 Creating the kickstart Slide 73

74 Creating the kickstart Under System Details/patitioning, set up the disk including LVM and RAID Slide 74

75 Creating the kickstart Slide 75

76 Creating the kickstart Under System Details/file preservation, define any files you want to be preserved when reprovisioning a server /etc/ssh is a good candidate Slide 76

77 Creating the kickstart Slide 77

78 Creating the kickstart Under Software/Package Groups define groups of packages you want installed Obtain them via comps.xml in RHEL 4 and earlier egrep "<name> packagereq" /usr/share/comps/[arch]/comps.xml Obtain them via yum grouplist in RHEL 5 and later Slide 78

79 Creating the kickstart Slide 79

80 Creating the kickstart Slide 80

81 Creating the kickstart Add packages by name Package groups symbol Exclude package by -name Slide 81

82 Creating the kickstart Slide 82

83 Creating the kickstart Activation Keys can be used to register systems to the right channel and enable monitoring and provisioning. Slide 83

84 Creating the kickstart Slide 84

85 Creating the kickstart Slide 85

86 Creating the kickstart The Scripts tab is used for pre-, postand post-nochroot scripts Slide 86

87 Creating the kickstart Slide 87

88 Viewing the kickstart Click on kickstart File to view the finished product There is no ks.cfg - the kickstart file is stored in the database and generated dynamically for presentation through a web interface. Slide 88

89 Viewing the kickstart Slide 89

90 anaconda-ks.cfg A template ks.cfg is created as /root/anaconda-ks.cfg after every installation Can be used as a foundation for future kickstarts Need to review, uncomment sections like partitioning Slide 90

91 anaconda-ks.cfg Slide 91

92 Kickstart on Bare Metal boot.iso vmlinuz and initrd.img Using DHCP and PXE Slide 92

93 boot.iso boot.iso is a boot CD image available on Red Hat and clone distros. Look on the CD or DVD ISO in /images You can either use it standalone and pass arguments to the installer (painful and error prone) or you can spin your own custom ISO and burn it or use it as virtual media (ilo, DRAC or similar) Slide 93

94 Stock boot.iso Burn the boot.iso file to media, pop it in the drive of the system you want to kickstart and pass the something like the following to the install kernel (all one line): linux text ks= ip= netmask= gateway= dns= If you have DHCP you can skip the ip, netmask, gateway and dns entries. Slide 94

95 Customizing boot.iso Mount the boot.iso file loopback and copy the contents to a temporary location. Use cp -r to capture the correct SELinux context. Something like this: Slide 95

96 Customizing the boot.iso Slide 96

97 Customizing boot.iso Edit the /isolinux/isolinux.cfg file Change default linux to default ks Change the append ks stanza to add in the ks=, ip=, netmask=, gateway= and dns= sections This removes human error Slide 97

98 Customizing the boot.iso Slide 98

99 Customizing the boot.iso Slide 99

100 Building your new boot.iso Delete any instances of the translation table from the my_iso directory find my_iso/ -name TRANS.TBL xargs rm Create your boot.iso using mkisofs: Slide 100

101 Customizing the boot.iso Slide 101

102 Building your new boot.iso Now boot with media created from myboot.iso to kickstart. Slide 102

103 initrd.img and vmlinuz You can also copy the initrd.img and vmlinuz from the /images/pxeboot directory on the boot.iso or CD1 or the ISO to /boot on a machine to be reinstalled. Add an install stanza in /boot/grub/grub.conf like this: Slide 103

104 grub.conf Slide 104

105 Kickstart via DHCP & PXE Required packages Setting up DHCP Setting up PXE Required Services Slide 105

106 Required Packages dhcp system-config-netboot bitmap-fonts xinetd tftp-server Slide 106

107 Setting up DHCP Using the sample dhcpd.conf file from /usr/share/doc/dhcp*/, create your DHCP config file in /etc Set at minimum: subnet declaration routers subnet mask domain name DNS servers range dynamic-bootp PXE stanza Slide 107

108 Sample dhcpd.conf ddns-update-style interim; ignore client-updates; subnet netmask { option routers ; option subnet-mask ; option domain-name "camerontech.net"; option domain-name-servers ; option time-offset ; # Central Standard Time option ntp-servers ; option netbios-name-servers ; range dynamic-bootp ; default-lease-time 21600; max-lease-time 43200; Slide 108

109 Sample dhcpd.conf (cont.) host molly { hardware ethernet 00:12:3f:5e:4b:a6; fixed-address ; } # For PXE next-server ; filename "/linux-install/pxelinux.0"; } Slide 109

110 Setting up PXE As root, run system-config-netboot Choose Network Installation dialog OS identifier and Description Protocol Kickstart location Server IP address Path to installation media Slide 110

111 Setting up PXE Slide 111

112 Setting up PXE This will copy the vmlinuz and initrd.img files from the install media to /tftpboot/linux-install/[os identifier] Slide 112

113 PXE Illustration Slide 113

114 Setting up PXE Make sure that the xinetd service is on Make sure that the tftp service is on Make sure that the dhcpd service is on Slide 114

115 Setting up PXE Slide 115

116 PXE Boot Slide 116

117 Kickstarting VMs From the command line From the GUI Slide 117

118 Kickstarting VMs /usr/sbin/virt-install is an interactive tool which will ask several questions Guest name Memory Disk location (file or partition backed) Enable graphics support (say no if installing via ssh) Install location (where is the installation media) Note that the command line provides more options Slide 118

119 virt-install Slide 119

120 virt-install Slide 120

121 virt-install Slide 121

122 Kickstarting VMs /usr/sbin/virt-manager is a graphical tool for setting up guests You can follow the prompts to install using kickstart Slide 122

123 virt-manager Slide 123

124 virt-manager Slide 124

125 virt-manager Slide 125

126 virt-manager Slide 126

127 virt-manager Slide 127

128 virt-manager Slide 128

129 virt-manager Slide 129

130 virt-manager Slide 130

131 virt-manager Slide 131

132 Amazon EC2 Time permitting, a live demo of provisioning an EC2 guest Slide 132

133 Questions? Slide 133

134 Thank You! This presentation is available at I can be contacted at thomas@redhat.com Slide 134