Centos Upgrade 4.x to 5.x

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To create a CentOS 5 minimal template from centos-4-i386-minimal, follow these steps:

Create the container

Create a container using centos-4-i386-minimal and set a valid nameserver:

vzctl create $CTID --ostemplate centos-4-i386-minimal --config CONFIG_TEMPLATE --ipadd container_IP --hostname temp
vzctl set $CTID --nameserver NAMESERVER_IP --save

Enter container

vzctl enter $CTID

Install centos-5-release packages

rpm -Uvh http://mirror.centos.org/centos/5/os/i386/CentOS/centos-release-notes-5.6-0.i386.rpm \ http://mirror.centos.org/centos/5/os/i386/CentOS/centos-release-5-6.el5.centos.1.i386.rpm

Note: centos-release-5 depends on notes-package, start with that one.

Backup dev

Backup your /dev/ directory, as initscripts needs udev and will remove vzdev you'll need the backup:

tar -cf dev.tar ./dev

Install initscripts package

Install initscripts package (forced and with no deps), as per below:

rpm -Uvh http://mirror.centos.org/centos/5/os/i386/CentOS/initscripts-8.45.33-1.el5.centos.i386.rpm --force --nodeps

Note: If the "transfer failed", go to the CentOS5 mirror and find the latest initscripts rpm and use that instead.

Exit from container

exit

Update conf file

Edit /etc/vz/conf/$CSID.conf and replace

OSTEMPLATE="centos-4-i386-minimal"

with

OSTEMPLATE="centos-5-i386-minimal"

Alternatively, use the 'sed' command to replace it:

sed -i 's#OSTEMPLATE="centos-4#OSTEMPLATE="centos-5#g' /etc/vz/conf/$CTID.conf

Copy existing template

Copy existing template from:

/vz/template/centos/4

to

/vz/template/centos/5

Update yum.conf

In /vz/template/centos/5/i386/config/yum.conf change mirrors to CentOS 5

Using sed:

sed -i 's#centos4#centos5#g' /vz/template/centos/5/i386/config/yum.conf
sed -i 's#CentOS 4#CentOS 5#g' /vz/template/centos/5/i386/config/yum.conf
sed -i 's#centos/4/#centos/5/#g' /vz/template/centos/5/i386/config/yum.conf

Upgrade container packages

db-version will complain, so delete the conflicting database first:

rm -fr /vz/root/$CTID/var/lib/rpm/__*

Now run vzyum to upgrade the contain packages:

vzyum $CTID upgrade

Troubleshooting

If you get this error:

Error: Missing Dependency: python-abi = 2.3 is needed by package python-elementtree

and/or

warning: rpmts_HdrFromFdno: Header V3 DSA signature: NOKEY, key ID e8562897
Public key for libsepol-1.15.2-3.el5.i386.rpm is not installed

You need to run the following before trying again:

vzctl exec $CTID rpm -e --justdb python-elementtree --nodeps
vzctl exec $CTID rpm --import http://mirrors.kernel.org/centos/RPM-GPG-KEY-CentOS-5

Test your VE

Check you can enter your VE:

vzctl enter $CTID

All went OK? Exit the VE:

exit

Troubleshooting

Unable to open pty: No such file or directory

If you see errors like this, see the VPS_enter_failed article.

Stop your VE

vzctl stop $CTID

Replace the new /dev/ with the old one

cd /vz/private/$CTID
mv dev dev.old
tar -xvf dev.tar

Remove container IP

vzctl set $CTID --ipdel all --save

Create the template

cd /vz/private/$CTID
tar --numeric-owner -zcf /vz/template/cache/centos-5.5-i386-minimal.tar.gz .