Forgot your password?
New user?
Document Actions
Afterworks
This document describes all afterworks to be done after having the sharedroot filesystem build but before the first boot.
Preface
This document describes all afterworks to be done after having the sharedroot filesystem build but before the first boot. All dependencies for the different distributions are described. Please choose these steps carefully.
Basically there are different thoughts to be taken into account.
First and most important the network interface(s) to be used for the root filesystem (including cluster communication) need to be excluded from any network configuration processes to be executed by the initprocess (see Network Tasks).
Most often there are also services that should not be running in a sharedroot environment. Those should be disabled if need be (see Services).
Also security services might be adapted or disabled to be running in a sharedroot environment (see Security).
General configuration tasks are described in the General section.
Network Tasks
The only and most important concern is/are the network interfaces to be used as requirement for the root filesystem. These should be adapted as required by the Linux distribution in use.
Red Hat based
Red Hat based Linux distributions are all Red Hat Enterprise Linux or Fedora based Linux distributions.
As there is no real description how to configure a network interface that is required for the root filesystem the best way is to remove the network configuration for the NIC in question and disable all services that might automatically bring up a default configuration for the NIC. This is to be done as follows.
- Remove NIC config (e.g. eth0)
rm /mnt/newroot/etc/sysconfig/network-scripts/ifcfg-eth0
- Disable the following services if they are available
- kudzu (chroot /mnt/newroot chkconfig kudzu off)
- Network manager (chroot /mnt/newroot chkconfig NetworkManager off)
ATTENTION: This might not be the optimum way to disable a NIC but still is the best working one. This might be changed in future when the initscripts and configuration files take this kind of usage into account.
SuSE based
As SuSE defines a configuration for NICs that are used for root filesystem they should be configured as follows.
Example for /mnt/newroot/etc/sysconfig/network/ifcfg-eth0
NM_CONTROLLED=no DEVICE="eth0" STARTMODE="nfsroot" TYPE="Ethernet"
Services
There are no services yet that need to be disabled in general.
Security
Red Hat based
Red Hat based Linux distributions are all Red Hat Enterprise Linux or Fedora based Linux distributions.
Security relevant are two things.
- First and foremost for GFS1/2 and OCFS2 SELinux always needs to be disabled. For this configure /mnt/newroot/etc/sysconfig/selinux as follows:
[root@install-node3 comoonics]# cat /mnt/newroot/etc/sysconfig/selinux # This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: # enforcing - SELinux security policy is enforced. # permissive - SELinux prints warnings instead of enforcing. # disabled - No SELinux policy is loaded. SELINUX=disabled # SELINUXTYPE= can take one of these two values: # targeted - Targeted processes are protected, # mls - Multi Level Security protection. SELINUXTYPE=targeted
2. Iptables should be disabled or configured as described in ports in use by redhat cluster or the services iptables and iptables6 are to be disabled.
chroot /mnt/newroot chkconfig iptables off chroot /mnt/newroot chkconfig iptables6 off
General
/etc/fstab
- The root filesystem entry entry should be removed from the /mnt/newroot/etc/fstab. An empty fstab might be look as follows
devpts /dev/pts devpts gid=5,mode=620 0 0 tmpfs /dev/shm tmpfs defaults 0 0 proc /proc proc defaults 0 0 sysfs /sys sysfs defaults 0 0
- The /boot filesystem entry (if apropriate) should be set to not to be mounted automatically.
/etc/mtab
Create '/mnt/newroot/etc/mtab' as a link to '/proc/mounts'
cd /mnt/newroot/etc/ rm -f mtab ln -s /proc/mounts mtab
Cron
Red Hat based
Red Hat based Linux distributions are all Red Hat Enterprise Linux or Fedora based Linux distributions.
- Because of cron running concurrently and processing unpredictable IOs by special cronjobs it is strongly recommended do disable (remove) the following cronjobs:
- makewhatis (rm /mnt/newroot/etc/cron.daily/makewhatis.cron)
- mlocate (rm /mnt/newroot/etc/cron.daily/mlocate.cron)
- prelink (rm /mnt/newroot/etc/cron.daily/prelink)
- Because of a deadlock and rpm database corruptions with berkeley db databases it is also important to disable (remove) the following cronjobs.
- rpm (rm /mnt/newroot/etc/cron.daily/rpm)
Initprocess
SuSE based
SuSE based Linux distributions are all SuSE Linux Enterprise or Open Suse based Linux distributions.
- Disable rootfsck and the like
rm /etc/init.d/boot.d/*boot.rootfsck
Fedora 11
For Fedora the patches for the initscripts are not automatically applied. That means if the clusternodes should shutdown in a normal way those patches need to be applied.
This works as follows
chroot /mnt/newroot /opt/atix/comoonics-bootimage/manage_chroot.sh -a patch_files
New Comoonics Productive Version Released !!