Creating a template cache : Slackware or HostGIS Linux

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Revision as of 16:29, 30 November 2007 by HostGIS (talk | contribs)
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Creating a new Host Template Cache for HostGIS Linux 4.x or Slackware 11.x/12.x

This process uses VMWare to install the OS into a VM, then to trim down the VM's contents to only those items suitable for a VPS/VE environment, then to save a snapshot of the system as a host template cache for use in OpenVZ.


          • CREATING THE VM

Start by creating a new VM in VMWare. The stats can be minimal, and there is no need to create the entire disk at once during the setup.

  * Create the disk as SCSI.

Then install HGL.

 * Create a small partition at the end of the disk for swap. Some swap
   is technically necessary, but since you'll never in fact be using it,
   a few MB should be fine.
 * Set the passwords to 'password'
 * Do set the timezone properly. The internal clock does not use UTC/GMT.
 * Select the default mouse, but do NOT enable GPM at startup.
 * Hostname:  template   Domain: internal.lan
 * IP config:  as appropriate for your LAN
 * Nameserver: no

Reboot into your new HGL install.

Now we want to tweak it into a usable template. Go ahead and login to the VM.


          • UPGRADES AND SECURITY PATCHES

The default HGL you used may require some software to be reinstalled, since new versions and critical bugfixes may have been released since that version of HGL was released. Follow these instructions, and also update them as necessary for the appropriate versions and to remove paragraphs when a revision of HGL comes out that no longer requires them.

  1. HGL 4.2 - no necessary upgrades as of Nov 29 2007


          • REPLACE INETD WITH XINETD

Inetd is good but minimal. Xinetd offers security features, such as restricting service to only certain IPs, and only listening on certain interfaces,.

removepkg inetd rm -f /etc/inetd.conf* /etc/rc.d/rc.inetd

cd /tmp wget --header="Host: xinetd.org" http://204.152.188.37/xinetd-2.3.14.tar.gz tar zxvf xinetd*.gz cd xinetd* ./configure --prefix=/usr --sysconfdir=/etc make && make install mkdir /etc/xinetd.d cat >> /etc/rc.d/rc.local <<EOF

  1. xinetd

/usr/sbin/xinetd EOF cat > /etc/xinetd.conf <<EOF defaults {

       log_type        = SYSLOG daemon notice
       log_on_success  = HOST EXIT DURATION
       log_on_failure  = HOST ATTEMPT
       instances       = 30
       cps             = 50 10

} includedir /etc/xinetd.d EOF


          • NAGIOS: THE HEALTH-MONITORING SYSTEM

groupadd nagios useradd -g nagios -d /usr/local/nagios -m nagios echo "nrpe 5666/tcp # Nagios NRPE" >> /etc/services

cd /tmp wget http://superb-east.dl.sourceforge.net/sourceforge/nagiosplug/nagios-plugins-1.4.10.tar.gz tar zxvf nagios-plugins-*.tar.gz ; cd nagios-plugins-* ./configure && make all && make install cd /tmp wget http://umn.dl.sourceforge.net/sourceforge/nagios/nrpe-2.10.tar.gz tar zxvf nrpe-2.10.tar.gz ; cd nrpe-2.10 ./configure && make && cp src/nrpe /usr/local/nagios/nrpe

for plugin in \

  check_wave check_users check_ups check_time check_tcp check_swap check_ssh check_ssmtp \
  check_spop check_simap check_smtp check_sensors check_rpc check_real check_pop check_ping \
  check_overcr check_oracle check_nwstat check_nt check_nntps check_nntp check_nagios \
  check_mysql_query check_mrtgtraf check_mrtg check_log check_jabber check_ircd \
  check_imap check_ifstatus check_ifoperstatus check_icmp check_http check_ftp check_flexlm \
  check_file_age check_dummy check_disk_smb check_dig check_dhcp check_clamd check_by_ssh \
  check_breeze check_apt check_udp

do rm -f /usr/local/nagios/libexec/$plugin ; done

cat > /usr/local/nagios/nrpe.cfg <<EOF

  1. NRPE Config File

pid_file=/var/run/nrpe.pid debug=0 command_timeout=60 connection_timeout=300

  1. And now the list of allowed check-commands:

command[check_disk]=/usr/local/nagios/libexec/check_disk -w 20% -c 10% -m / command[check_dns]=/usr/local/nagios/libexec/check_dns www.google.com command[check_load]=/usr/local/nagios/libexec/check_load -w 5,5,5 -c 8,8,8 command[check_mailq]=/usr/local/nagios/libexec/check_mailq -w 10 -c 20 command[check_mysql]=/usr/local/nagios/libexec/check_mysql -d gisdata -H localhost -u gisdata -p password command[check_pgsql]=/usr/local/nagios/libexec/check_pgsql -d gisdata -H localhost -l gisdata -p password command[check_ntp]=/usr/local/nagios/libexec/check_ntp -H pool.ntp.org command[check_crond]=/usr/local/nagios/libexec/check_procs -u root -c 1: --command=crond command[check_syslogd]=/usr/local/nagios/libexec/check_procs -u root -c 1:1 --command=syslogd command[check_xinetd]=/usr/local/nagios/libexec/check_procs -u root -c 1:1 --command=xinetd EOF

cat > /etc/xinetd.d/nrpe <<EOF

  1. description: NRPE for Nagios

service nrpe {

  socket_type     = stream
  protocol        = tcp
  wait            = no
  user            = nagios
  server          = /usr/local/nagios/nrpe
  server_args     = -c /usr/local/nagios/nrpe.cfg --inetd
  only_from       = __HOSTIP__

} EOF

chown -R nagios:nagios /usr/local/nagios chmod -R o-rwx /usr/local/nagios chmod go-rwx /etc/xinetd.d



          • OTHER UNNECESSARY STUFF
  1. kernel, kernel modules, documentation, mount points

rm -rf /lib/modules /boot /dev/.udev /usr/doc /usr/info /media

  1. packages not applicable to a VPS setting, or which we don't use at HostGIS
  2. e.g. phpMyAdmin and phpPgAdmin are security holes

cd /var/log/packages for pkg in \

  hotplug-* hdparm-* devmapper-* udev-* usbutils-* pciutils-* module-init-tools-* \
  mdadm-* floppy-* lvm2-* phpMyAdmin-* phppgAdmin-* raidtools-* reiserfsprogs-* \
  smartmontools-* sysfsutils-* syslinux-* wireless_tools.* quota-* iptables-*

do removepkg $pkg ; done

  1. most folks don't use GeoServer, so disable it by default

chmod 644 /etc/rc.d/rc.geoserver

  1. prune init's getty

vi /etc/inittab # delete everything after entry l6 (runlevel 6) init q

  1. clean out the fstab and mtab files

( cd /etc ; rm -f fstab mtab ; ln -s ../proc/mounts mtab ) echo "proc /proc proc defaults 0 0" >> /etc/fstab echo "devpts /dev/pts devpts mode=0620 0 0" >> /etc/fstab

  1. the startup sequence and services, even the firewall

cd /etc/rc.d rm -f rc.gpm-sample rc.hotplug rc.ip_forward rc.modules rc.scanluns rc.serial rc.udev rc.sysvinit rc.firewall vi rc.syslog # delete all mentions of klogd vi rc.local # delete smartd and inetd vi rc.M # delete the setterm entry vi rc.S # delete the MOTD clobbering

  1. blow away the network configuration with dummy strings for later replacement
  2. replace the IP address with __IPADDRESS_
  3. replace the netmask with __NETMASK__
  4. replace the GATEWAY with __GATEWAY__

vi /etc/rc.d/rc.inet1.conf


          • BASIC FILE SECURITY SETTINGS
  1. clear out old/dummy SSL certificates

mv /etc/ssl/openssl.cnf /tmp ; rm -r /etc/ssl/* ; mv /tmp/openssl.cnf /etc/ssl

  1. fix file permissions

find / -mount -nouser -exec chown root {} \; & find / -mount -nogroup -exec chgrp root {} \; & for i in \

  /bin/ping /bin/mount /bin/ping6 /bin/umount /usr/bin/chfn \
  /usr/bin/chsh /usr/bin/crontab /usr/bin/chage /usr/bin/traceroute6 /usr/bin/traceroute \
  /usr/bin/expiry /usr/bin/newgrp /usr/bin/passwd /usr/bin/gpasswd \
  /usr/libexec/ssh-keysign /usr/libexec/pt_chown /usr/bin/wall /usr/bin/write
  do chmod u-s $i ; done
  1. fix Apache's configuration:
  2. add ServerTokens prod
  3. go to the htdocs Directory definition and change Indexes to -Indexes
  4. delete the entries for phpmyadmin and phppgadmin

vi /etc/apache/httpd.conf

  1. keep FTP users chrooted:

echo "" >> /etc/proftpd.conf echo "# keep all users chrooted to their homedir" >> /etc/proftpd.conf echo "DefaultRoot ~" >> /etc/proftpd.conf

  1. allow the mailq to be checked by anybody:

chgrp smmsp /var/spool/mqueue chmod g+rx /var/spool/mqueue

  1. disable the root and user accounts
  2. by changing the password for root and user to a ! character.

vi /etc/shadow


          • REBOOTING

A VPS cannot actually reboot, since there's no power switch to power-cycle the machine after the VE has been shut down. OpenVZ emulates this effect with an external cronjob called vpsreboot (see /etc/cron.d/vz). In order to reboot a VPS that has been shut down and which is expecting a reboot, the shutdown sequence must create a file named /reboot in the VPS's filesystem.

Also, the /etc/mtab file should point to /proc/mounts so it can detect the / filesystem.

vi /etc/rc.d/rc.6 And add these two lines near the start:

  1. create the reboot flag so we get rebooted automatically

touch /reboot

vi /etc/rc.d/rc.M And add these two lines near the start:

  1. replace the mtab file with a link to /proc/mounts so OpenVZ can find the / filesystem

rm -f /etc/mtab ; ln -s /proc/mounts /etc/mtab


          • DELETING AND BLANKING SETTINGS

Lastly, you'll want to delete or blank out a bunch of files so they start fresh when the VE is booted for its first time.

  1. stop all services

apachectl stop killall syslogd klogd udevd crond /etc/rc.d/rc.sendmail stop /etc/webmin/stop /etc/rc.d/rc.pgsql stop /etc/rc.d/rc.mysqld stop killall named proftpd killall xinetd

  1. refresh the 'locate' cache

/etc/cron.daily/slocate

  1. blank out the system logfiles

for logfile in \

   /var/log/messages /var/log/syslog /var/log/debug /var/log/secure \
   /var/log/maillog /var/log/spooler /var/log/proftpd.log /var/log/xinetd.log \
   /var/log/dmesg /var/log/faillog /var/log/lastlog /var/log/wtmp \
   /var/log/apache/access_log /var/log/apache/error_log \
   /var/log/webmin/miniserv.error /var/log/webmin/miniserv.pid

do cp /dev/null $logfile ; done rmdir /var/log/sa

  1. clear the SSH host key

rm -f /etc/ssh/ssh_host_*

  1. database server logfiles

rm -f /var/lib/mysql/*.err /var/lib/pgsql/logfile

  1. delete vi backup files, bash_history files, and other small application crud

unset HISTFILE find / -name '*~' \

   -o -name .bash_history \
   -o -name .gnupg \
   -o -name .lesshst \
   -o -name .viminfo \
   -o -name .rnd \
   -delete
  1. the junk under /tmp

rm -rf /tmp/*



          • CREATING THE VE CACHE IMAGE

A VE cache is just a tar.gz file of the entire filesystem. So creating them is simple!

tar zcvf /tmp/HostGIS_Linux_4.2_64bit.tar.gz --exclude='/sys/*' --exclude='/proc/*' --exclude='/tmp/*' /

Ta-da! That's your new VE template cache. Just SFTP it to the VE server and you're all set!