Because xen virtualization will be replace by kvm on rhel6 so I have to migrate my server that running on xen virtual machine to kvm. after search on internet that have many documents and method to convert xen guest to kvm, I test migrate by manual method which is working well and easy to migrate.

My environment, I am running rhel5 xen kernel 2.6.18-92 guest and migrate to host running on the rhel5 kernel 2.6.18-168

Here are steps to migrate to kvm virtualization

1. comment HWADDR line on /etc/sysconfig/network-scripts/ifcfg-

2. change xvc0 to ttyS0 (if exist) in /etc/inittab, /etc/securetty, /boot/grub/grub.conf

3. change /dev/xvda (xvdb etc..) to /dev/hda (in case no virtio drivers or /dev/vda with virtio) in /boot/grub/device.map, /etc/fstab

if you map device with partition label (LABEL=SWAP-sda2 /swap in fstab for example) you can change partition lable with command "e2label " to match new partition

4. change to boot with standard kernel, modify from DEFAULTKERNEL=kernel-xen in /etc/sysconfig/kernel to DEFAULTKERNEL=kernel

you have to yum kernel with "yum install kernel" or "yum localinstall "

change /etc/modprobe.conf replace xen with virtio

build new ramdisk with "mkinitrd -v -f --with=virtio_pci --builtin=xenblk path-to-initrd kernel-version"

5. on kvm virtual machine host make it boot with default kernel by install kernel (if still be xenkernel) and change DEFAULTKERNEL=kernel

6. run #setenforce 0

7. create network bridge on kvm host

8. copy image from xen host to new kvm host

9. create new kvm virtual guest with virt-manager (specify copy image path) and abort when it start new installation (use virt-manager only for create xml file)

10. modify xml file with "virsh edit " replace dev=hda to dev=vda and bus=ide to bus=virtio (in case use virtio)


It's done. start new kvm guest, remove or configure new device in kvm virtualization guest. now you already migrate Xen guest virtual machine to linux KVM virtualization

For change upload limit for php, you have to change upload_max_filesize, memory_limit and post_max_size parameters in php.ini (/etc/php.ini - linux) then restart apache server (service httpd restart).

someone said that post_max_size and memory_limit need to be larger than upload_max_filesize.

Today i testing moodle on my server and try to upload video file about 200MB.

For change upload file size i have to change upload_max_filesize and post_max_size on php.ini.

After that I try to upload avi file and get error and cant login to moodle anymore so i think it has something wrong about session.

after searching ppl say that have to change dbsession in mdl_config table so i try to change it in mysql database but i get error "You probably tried to upload too large file. Please refer to documentation for ways to workaround this limit."

The reason of error is i wrong config in php.ini that i should change 3 parameters upload_max_filesize, post_max_size and memory_limit , so when i change all of parameters my moodle system working fine.

Today I will test buddypress on WP 3.0 so I install new WP and buddypress on my localhost testing system, after finish install i get HTTP ERROR 404 NOT FOUND so I searching for the solution.

In my case, fix it by:

change http.conf to use mod rewrite by uncomment line

#LoadModule rewrite_module modules/mod_rewrite.so

then change "AllowOverride None" to "AllowOverride All"

# AllowOverride controls what directives may be placed in .htaccess files.
# It can be "All", "None", or any combination of the keywords:
# Options FileInfo AuthConfig Limit
#
AllowOverride All


after change apache config you have to restart apache.. done


another reason that may happen is wordpress can't write .htaccess in wordpress directory when you change permalink in wordpress setting

solution is change .htaccess file permission from 644 to 666 then change permalink setting from wordpress dashboard, after that change file permission back to 644.

wordpress will write new access rule to .htaccess according to your setting correctly



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For connect SAP from php program you have to install saprfc which you can download here http://saprfc.sourceforge.net

Install saprfc on linux you have 2 option, rebuild php with saprfc extension or use dynamic module - this blog using dynamic module for configure saprfc

Install RFCSDK

1. First you have to download SAP RFCSDK from http://service.sap.com/swdc (Support Packages and Patches - Entry by Application Group - Additional Components - SAP RFC SDK)

2. unpack RFC_xxxxxxxxxx.SAR with SAPCAR

3. mv rfcsdk to /opt/rfcsdk

3. set environment variable LD_LIBRARY_PATH=/opt/rfcsdk/lib


Install SAPRFC

1. unpack saprfc-1.4.1.tar.gz

2. cd

3. # phpize
# ./configure
# make
# make install

4. insert line "extension=saprfc.so" in php.ini

install java SDK:
download jdk-6u18-linux-x64-rpm.bin from http://java.sun.com/javase/downloads/widget/jdk6.jsp
#./jdk-6u18-linux-x64-rpm.bin


install TOMCAT:
download apache-tomcat-6.0.26.tar.gz from http://tomcat.apache.org/download-60.cgi

unpack tar -xvzf http://tomcat.apache.org/download-60.cgi

move /apache-tomcat-6.0.26 to decide directory such as /opt/tomcat/

set environment variable:
PATH=/usr/java/jdk1.6.0_18/bin:$PATH
CATALINA_HOME=/opt/tomcat
JAVA_HOME=/usr/java/jdk1.6.0_18 <- path to java sdk

set TOMCAT to run as unix daemon:

cd $CATALINA_HOME/bin
tar xvfz jsvc.tar.gz
cd jsvc-src
autoconf
./configure
make
cp jsvc ..
cd ..

command to run tomcat as daemon:

$CATALINA_HOME/bin/jsvc -cp ./bin/bootstrap.jar \
-outfile ./logs/catalina.out -errfile ./logs/catalina.err \
org.apache.catalina.startup.Bootstrap

add user in file $CATALINA_HOME/conf/tomcat-users.xml

download mysql odbc from http://www.mysql.com/downloads/connector/odbc/

install rpm package rpm -Uvh xxx.rpm

insert line to /etc/odbcinst.ini

# Driver from the MyODBC package
# Setup from the unixODBC package
[MySQL]
Description = ODBC for MySQL
Driver = /usr/lib64/libmyodbc5-5.1.5.so <- path to mysql odbc lib
Setup = /usr/lib64/libodbcmyS.so
FileUsage = 1

insert line to /etc/odbc.ini

connector name = MyODBC 5.5 Driver DSN

[connector name]
Description = ODBC for MySQL
Driver = MySQL
SERVER = ip mysql database server
USER = user
PASSWORD =
PORT = 3306
DATABASE = database name
OPTION = 3