Xen 4.4: How to configure dom0 and domu with different ip subnet in Debian Jessie

Dom0 and domu has different subnet and dom0 act as router

• Dom0 has A.B.C.81 with netmask 255.255.255.0.
• Domu has ip range X.Y.X.144 - X.Y.Z.151 netmask 255.255.255.248.

OVH inform us, this ip range (X.Y.X.144 - X.Y.Z.151) will be reroute via A.B.C.81. It means, br0 becomes a gateway for domu.

Continue from http://dedetoknotes.blogspot.co.id/2016/05/how-to-install-xen-in-debian-jessie.html 

Solution: 

This is text diaagram for paritcular case:

A.B.C.254 ---- A.B.C.81
(Gateway)       (br0/dom0)
                       X.Y.X.150 ---- X.Y.X.144 - X.Y.Z.149 (domu)
                         (br1/dom0)

List of ip can not be used for domu 

• X.Y.X.144 as address 
• X.Y.X.151 as broadcast
• X.Y.X.150 OVH ask me to assign this ip as a gateway

I create a new bridge network br1 which does not attach to any physical device and assign it as router with ip Z.Y.Z.150:

# brctl addbr br1
# ifconfig br1 Z.Y.Z.150 netmask 255.255.255.248 up
# brctl stp br1 on (optional)

Here is a new bridge configuration:

# brctl show
bridge name     bridge id               STP enabled     interfaces
br0             8000.e03f49e8149b       yes             eth0
br1             8000.feffffffffff       no              vif2.0
virbr0          8000.000000000000       no

Here is route output:

# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         A.B.C.254  0.0.0.0         UG    0      0        0 br0
A.B.C.0    *               255.255.255.0   U     0      0        0 br0
192.168.0.0     *               255.255.255.0   U     0      0        0 virbr0
X.Y.X.144  *               255.255.255.248 U     0      0        0 br1

You can create your domu using xen-create-image with ip range from X.Y.X.145 to X.Y.X.149 and br1 as bridge network. This is an example:

# xen-create-image --hostname test --size=10GB --swap=1024MB --memory=512MB --vcpu=1 --dist=jessie --ip=Z.Y.Z.145 --netmask=255.255.255.248 --gateway=Z.Y.Z.150 --bridge=br1

Ping reply from outside (public) after dom0 make internal process to reroute from br0 into br1:

>ping x.y.z.145

Pinging x.y.z.145 with 32 bytes of data:
Reply from x.y.z.145: bytes=32 time=276ms TTL=50
Reply from x.y.z.145: bytes=32 time=270ms TTL=50
Reply from x.y.z.145: bytes=32 time=288ms TTL=50
Reply from x.y.z.145: bytes=32 time=269ms TTL=50

Ping statistics for x.y.z.145:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 269ms, Maximum = 288ms, Average = 275ms

To make it permanent, add br1 into /etc/network/networking in dom0:

auto br1
iface br1 inet static
        address X.Y.X.150
        netmask 255.255.255.248
        broadcast X.Y.X.151
   pre-up brctl addbr br1

References (thanks):

• http://www.linuxforums.org/forum/newbie/186273-iptables-forwarding-vs-ip-route.html 
• http://www.linuxquestions.org/questions/linux-networking-3/routing-between-interfaces-217543/ 
• http://www.linuxquestions.org/questions/linux-networking-3/network-routing-between-two-networks-problem-569978/ 
• http://www.linuxquestions.org/questions/linux-networking-3/how-to-route-ip-packets-between-ethernet-bridges-725543/ 
• http://askubuntu.com/questions/581771/kvm-create-a-virtual-machine-with-2-bridges-interfaces 
• http://serverfault.com/questions/529963/bridged-network-setup-with-gateway-not-in-netmask 
• https://help.ubuntu.com/community/Xen 
• https://debian-administration.org/article/360/An_introduction_to_custom_Xen_networking 
• http://www.pocketnix.org/posts/Linux%20Networking%3A%20Dummy%20Interfaces%20and%20Virtual%20Bridges 
• http://unix.stackexchange.com/questions/152331/how-can-i-create-a-virtual-ethernet-interface-on-a-machine-without-a-physical-ad 
• http://forums.debian.net/viewtopic.php?f=5&t=49303 
• http://linux-vserver.org/Networking_vserver_guests 
• http://wiki.networksecuritytoolkit.org/nstwiki/index.php/Dummy_Interface 
• https://systemausfall.org/wikis/howto/XenUpgrade3.2#Dummy_network_interfaces_stopped_working 
• http://jodies.de/ipcalc 

Odoo: Installation problems

Symptom: FATAL:  role "odoo" does not exist

Solution:

You need to create postgresql user with name odoo. As root create postgresql user:

# su - postgres -c "createuser -s odoo"

Symptom: new encoding (UTF8) is incompatible with the encoding of the template database (SQL_ASCII)

Solution:

Alter postgresql encoding.

# su postgres

$ psql postgres
psql (9.6.4)
Type "help" for help.

postgres=# update pg_database set datallowconn = TRUE where datname = 'template0';
UPDATE 1
postgres=# \c template0
You are now connected to database "template0" as user "postgres".
template0=# update pg_database set datistemplate = FALSE where datname = 'template1';
UPDATE 1
template0=# drop database template1;
DROP DATABASE
template0=# create database template1 with template = template0 encoding = 'UTF8';
CREATE DATABASE
template0=# update pg_database set datistemplate = TRUE where datname = 'template1';
UPDATE 1
template0=# \c template1
You are now connected to database "template1" as user "postgres".
template1=# update pg_database set datallowconn = FALSE where datname = 'template0';
UPDATE 1
template1=# \q

References:

• https://www.odoo.com/forum/help-1/question/dataerror-new-encoding-utf8-is-incompatible-with-the-encoding-of-the-template-database-sql-ascii-52124

Xen 4.4: How to install in Debian Jessie

Ideal environment:

• sda1 - /boot 200MB
• sda2 - / 15GB
• sda3 - swap
• sda4 - reserved for LVM

Check CPU support 

# egrep '(vmx|svm)' /proc/cpuinfo

Install clock synchronize

# apt-get install ntp

Install network bridge utility

# apt-get install bridge-utils

Install Xen 

# apt-get install xen-linux-system

# apt-get install xen-hypervisor-4.4-amd64

# apt-get install xen-tools

# apt-get install qemu-system-x86

Make kernel for Xen active

find ### BEGIN /etc/grub.d/20_linux_xen ### in /boot/grub/grub.cfg

# vi /boot/grub/grub.cfg

### BEGIN /etc/grub.d/20_linux_xen ### 

menuentry 'Debian GNU/Linux, with Xen hypervisor' 

Edit /etc/default/grub

# vi /etc/default/grub

GRUB_DEFAULT='Debian GNU/Linux, with Xen hypervisor'

update grub 

# update-grub

Restart to activate Xen kernel, check your Xen

# xl list

Name                                        ID   Mem VCPUs      State   Time(s)

Domain-0                                     0 32167     8     r-----     110.6

Configure bridge network:

Edit /etc/network/interfaces

# vi /etc/network/interfaces

...

auto eth0

iface eth0 inet manual

auto br0

iface br0 inet static

        address [ipv4]

        netmask [netmask]

        network [network]

        broadcast [broadcast]

        gateway [ipv4gateway]

        bridge_ports eth0

        bridge_stp on

        bridge_maxwait 0

iface br0 inet6 static

        address [ipv6]

        netmask 64

        dns-nameservers [dnsipv6]

        gateway [ipv6gatewaay]

        autoconf 0

# internal

auto virbr0

iface virbr0 inet static

        address 192.168.0.1

        netmask 255.255.255.0

        broadcast 192.168.0.255

        pre-up brctl addbr virbr0

edit /etc/sysctl.conf.d

net.ipv4.ip_forward = 1

net.ipv6.conf.all.forwarding=1

net.bridge.bridge-nf-call-ip6tables = 0

net.bridge.bridge-nf-call-iptables = 0

net.bridge.bridge-nf-call-arptables = 0 

Manual adding virbr0

# brctl addbr virbr0

# ifconfig virbr0 192.168.0.1 netmask 255.255.255.0 up  

Install and configure dhcp server for domu

Install isc-dhcp-server 

# apt-get install isc-dhcp-server 

Edit /etc/default/isc-dhcp-server

INTERFACES="virbr0"

Edit /etc/dhcp/dhcpd.conf

subnet 192.168.0.0 netmask 255.255.255.0 {

  range 192.168.0.10 192.168.0.50;

  option routers 192.168.0.1;

  default-lease-time 600;

  max-lease-time 7200;

}

Restart dhcp server

# service isc-dhcp-server restart

Configuring xen-tool to create domu images

edit /etc/xen-tools/xen-tools.conf

#Begin by setting the dir = directive to the directory into which the tools are to create the Xen guest image files:

dir = /home/images

#lvm = myvolgroup -> if using LVM (logical volume management)

install-method = debootstrap

debootstrap-cmd = /usr/sbin/debootstrap

size   = 4G       # Root disk, suffix (G, M, k) required

memory = 512M # Suffix (G, M, k) required

swap   = 1G # Suffix (G, M, k) required

fs     = ext3     # Default file system for any disk

dist   = `jessie` # Default distribution is determined by Dom0's distribution

image  = sparse   # Specify sparse vs. full disk images (file based images only)

# for static

# gateway    = 192.168.1.1

# netmask    = 255.255.255.0

# broadcast  = 192.168.1.255

dhcp=1

bridge = virbr0

genpass_len = 8

passwd = 1

kernel      = /boot/vmlinuz-`uname -r`

initrd      = /boot/initrd.img-`uname -r`

pygrub = 1

mirror = http://debian.mirrors.ovh.net/debian

mirror_jessie = http://http.debian.net/debian

ext4_options     = noatime,nodiratime,errors=remount-ro 

ext3_options     = noatime,nodiratime,errors=remount-ro

ext2_options     = noatime,nodiratime,errors=remount-ro

xfs_options      = defaults

reiserfs_options = defaults

btrfs_options    = defaults

output    = /etc/xen

extension = .cfg

Creating Xen disk image (loopback image) for Xen guest

Create xen guest with hostname testa, disk 10G, swap 1G, ram/memory 512M, dhcp, vcpu 3, OS Debiean jessie:

# xen-create-image --hostname testa --size=10Gb --swap=1024Mb --memory=512Mb --vcpu=3  --dist=jessie

Can't exec "jessie": No such file or directory at /usr/share/perl5/Xen/Tools/Common.pm line 100, <FILE> line 134.

Use of uninitialized value $output in scalar chomp at /usr/share/perl5/Xen/Tools/Common.pm line 101, <FILE> line 134.

Use of uninitialized value $output in concatenation (.) or string at /usr/share/perl5/Xen/Tools/Common.pm line 104, <FILE> line 134.

General Information

--------------------

Hostname       :  testa

Distribution   :  jessie

Mirror         :  http://debian.mirrors.ovh.net/debian

Partitions     :  swap            1024Mb (swap)

                  /               10Gb  (ext3)

Image type     :  sparse

Memory size    :  512Mb

Bootloader     :  pygrub

Networking Information

----------------------

IP Address     : DHCP [MAC: 00:16:3E:73:6F:31]

Creating partition image: /home/vmimages/domains/testa/swap.img

Done

Creating swap on /home/vmimages/domains/testa/swap.img

Done

Creating partition image: /home/vmimages/domains/testa/disk.img

Done

Creating ext3 filesystem on /home/vmimages/domains/testa/disk.img

Done

Installation method: debootstrap

Done

Running hooks

Done

No role scripts were specified.  Skipping

Creating Xen configuration file

Done

No role scripts were specified.  Skipping

Setting up root password

Enter new UNIX password:

Retype new UNIX password:

passwd: password updated successfully

All done

Logfile produced at:

         /var/log/xen-tools/testa.log

Installation Summary

---------------------

Hostname        :  testa

Distribution    :  jessie

MAC Address     :  00:16:3E:73:6F:31

IP Address(es)  :  dynamic

RSA Fingerprint :  21:12:bb:c3:ad:34:67:6f:cd:a1:7d:d3:ef:ae:95:f5

Root Password   :  N/A

This process take approximate 14 minutes.

Run xen guest 

To run xen guest 

# xl create /etc/xen/testa.cfg -c

xl command 

To list dom0 and domu

# xl list

To start domu

# xl create /etc/xen/[config].cfg 

To destroy domu

# xl destroy test

To shutdown domu

# xl shutdown test

To show xen information

# xl info

To show cpu use

# xl vcpu-list

Allocate memory and cpu for dom0

To show grub version

 # grub-install --version

grub-install (GRUB) 2.02~beta2-22+deb8u1

Allocate memory for dom0 between 1024M and maximum 4048M  

• for grub1 (/boot/grub/grub.conf or /boot/grub/menu.lst)

  title Xen 4.1.0 / pv_ops dom0 kernel 2.6.32.36

    root (hd0,0)

    kernel /xen-4.0.gz dom0_mem=1024M,max:4048M loglvl=all guest_loglvl=all

    module /vmlinuz-2.6.32.36 ro root=/dev/sda2 console=hvc0 earlyprintk=xen nomodeset

    module /initrd-2.6.32.36.img

• for grub2 (/etc/default/grub)

  GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=1024M,max:4048M"

In general you should not assigned less than 4 vCPUs to Dom0

dom0_max_vcpus=4 dom0_vcpus_pin

Routing

Internal to internet

# iptables -t nat -A POSTROUTING -o br0 -j MASQUERADE

# iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

# iptables -A FORWARD -i virbr0 -o br0 -m state --state RELATED,ESTABLISHED -j ACCEPT

# iptables -A FORWARD -i virbr0 -o br0 -j ACCEPT  

Internet to internal in port xxx into 192.168.0.100 port yyy

# iptables -A PREROUTING -t nat -i br0 -p tcp --dport xxx -j DNAT --to 192.168.0.100:yyy

# iptables -A FORWARD -p tcp -d 192.168.0.100 --dport yyy -j ACCEPT

Make auto-start domu after boot

Create symlink into folder /etc/xen/auto

# mkdir /etc/xen/auto

# cd /etc/xen/auto/

# ln -s /etc/xen/testa.cfg

 

edit /etc/xen/testa.cfg

# vi /etc/xen/testa.cfg

on_xend_stop='shutdown' 

on_xend_start='start'

Additonal Note 

Manual create disk image and swap image

Create 10 G image disk

# fallocate -l 10G /home/vmimages/test1/disk1.img

or using dd (slower)

# dd if=if=/dev/zero of=/xen/test1/disk1.img bs=1gb count=0 seek=10

or using qemu-img

# qemu-img create -f raw -o size=8G /home/vmimages/test1/disk1.raw

Formatting '/home/vmimages/test1/disk1.raw', fmt=raw size=8589934592

Preparing image in ext4 file system

# mkfs -t ext4 /home/vmimages/test1/disk1.img

Create 1 G image swap

# fallocate -l 1G /home/vmimages/test1/swap.img

Preparing image swap

# mkswap /home/vmimages/test1/swap.img

Create partition on image disk

# fdisk /home/vmimages/domains/test/disk.img

Command (m for help): n

Partition type

   p   primary (0 primary, 0 extended, 4 free)

   e   extended (container for logical partitions)

Select (default p): p

Partition number (1-4, default 1): 1

First sector (2048-8388607, default 2048):

Last sector, +sectors or +size{K,M,G,T,P} (2048-8388607, default 8388607):

Created a new partition 1 of type 'Linux' and of size 4 GiB.

Command (m for help): a

Selected partition 1

The bootable flag on partition 1 is enabled now.

Command (m for help): p

Disk /home/vmimages/domains/test/disk.img: 4 GiB, 4294967296 bytes, 8388608 sectors

Units: sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disklabel type: dos

Disk identifier: 0x05824062

Device                                Boot Start     End Sectors Size Id Type

/home/vmimages/domains/test/disk.img1 *     2048 8388607 8386560   4G 83 Linux

Command (m for help): w

The partition table has been altered.

Syncing disks.

# file /home/vmimages/domains/test/disk.img

/home/vmimages/domains/test/disk.img: DOS/MBR boot sector; partition 1 : ID=0x83, active, start-CHS (0x0,32,33), end-CHS (0x2a,42,32), startsector 2048, 8386560 sectors

References:

• https://wiki.debian.org/Xen  
• http://wiki.xen.org/wiki/Debian_Guest_Installation_Using_Debian_Installer 
• http://wiki.xen.org/wiki/PvGrub 
• http://xenbits.xen.org/docs/4.4-testing/man/xl.cfg.5.html 
• https://wiki.debian.org/Xen 
• https://wiki.debian.org/PvGrub 
• http://ftp.debian.org/debian/dists/stable/main/installer-amd64/current/images/cdrom/xen/debian.cfg 
• http://wiki.xenproject.org/wiki/Xen_Project_Beginners_Guide 
• http://wiki.xenproject.org/wiki/Xen_Common_Problems 
• http://wiki.xenproject.org/wiki/Tuning_Xen_for_Performance 
• http://wiki.xenproject.org/wiki/Xen_Project_4.4_Man_Pages 
• https://help.ubuntu.com/community/Xen 
• https://tipstricks.itmatrix.eu/category/linux-tips/xen-tips/ 
• https://screenzone.eu/howto-xen-4-4-debian-hetzner/ 
• http://www.virtuatopia.com/index.php/Building_a_Xen_Virtual_Guest_Filesystem_on_a_Disk_Image_(Cloning_Host_System) 
• http://backdrift.org/xen-pvgrub-howto 
• http://xmodulo.com/install-xen-hypervisor.html 
• http://wiki.libvirt.org/page/Networking  
• https://jamielinux.com/docs/libvirt-networking-handbook/bridged-network.html  
• http://man.cx/xen-create-image  
• https://wiki.archlinux.org/index.php/xen 
• https://blog.filippo.io/converting-a-partition-image-to-a-bootable-disk-image/ 
• http://askubuntu.com/questions/196444/how-do-i-auto-start-xen-guests-on-boot 
• https://andreas.scherbaum.la/blog/archives/871-Autostart-XEN-Domains.html 
• http://www.systutorials.com/816/port-forwarding-using-iptables/