zSync Requirements

rSync Requirements

• Rsync (Daemon)
• SSH Server
  • With Public Key authentication enabled

Virtual Machine

Technically, it is very possible, and a fine option to simply take the Virtual Machine listed above for Windows Hosts.
Still, if you prefer to run Rsync/SSH directly on your server, please read below.
To run the VM as non root user you will need to adjust the HostPort's to above 1024 though.

Example: Ubuntu 9.10 Server edition

These are the instructions I use. You can leave out shorewall (firewall), wondershaper (bandwidth limiter), and the fstab parts.

sudo bash

apt-get update && apt-get install rsync
# optional: apt-get dist-upgrade
# optional: apt-get install shorewall-common shorewall-shell wondershaper mc ruby1.9.1 rubygems1.9.1 ruby1.9.1-dev build-essential && apt-get autoremove

# optional: ln -s /usr/bin/ruby1.9.1 /usr/bin/ruby
useradd -m rsync
mkdir -p /var/scm/rsync
chown -R rsync:rsync /var/scm/rsync
ln -s /var/scm/rsync /home/rsync/repositories
chown -R rsync:rsync /home/rsync/repositories
sudo -H -u rsync mkdir /home/rsync/.ssh
sudo -H -u rsync pico /home/rsync/.ssh/authorized_keys

update-rc.d rsync defaults
# optional: update-rc.d shorewall defaults

# Manually set rsync startup (RSYNC_ENABLE) and configuration
pico /etc/default/rsync && pico /etc/rsyncd.conf
# optional, TODO: Firewall Configuration missing... && pico /etc/default/shorewall
# optional: pico /etc/fstab && mount /var/scm/rsync
mkdir /var/scm/rsync/rel
chown -R rsync:rsync /var/scm/rsync

File: /home/rsync/.ssh/authorized_keys

no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA86sYqRjHBoOsMCFZwfWHNg7xGdA+dI2e1rWEWEyU0VoWf+mO7XMupZk5uSs8AHT0fY4pvIGyjCqH3Vj3F68d4AkteFXKm+2e6sizPwMls8WJavUmZAEgQGQJMWG+AkOw4G/kdUvMWAy50Rv6yQddgbodAq2FQzo6X+ESWJPcgl8olrxAmptT4SgDE4WNTAcSa3I80lo38cVUgkLqr8+witfx+g4lOjapkL7SSorXLJYfsPXFJ9jCCzXPZu22KYeeNq7Y4Cvt8DpOyMdpwENZt48CcDkG/SrV0hUNnZNMhxWXyNHGpGphyyzn7Fwlsgm1b6SwaOao+OU7oCG3yayUVw== rsync_tool

File: /etc/rsyncd.conf

motd file = /etc/rsyncd.motd #Below are actually defaults, but to be on the safe side...
read only = yes
list = yes
uid = rsync
gid = rsync

log file = /var/log/rsync.log
secrets file = /etc/rsyncd.secrets

max connections = 25

[rel]
path = /var/scm/rsync/rel
#read only = no

Example: RedHat Enterprise Linux 5/CentOS 5

Here's how to configure a rsync service on RHEL5/CentOS 5. It's a slight variation on the way it was done in Ubuntu Server above.

Installation and configuration

1. Create the rsync user and set a good password for the account

   [root@localhost ~]# useradd -m rsync
   [root@localhost ~]# passwd rsync
   Changing password for user rsync.
   New UNIX password: 
   Retype new UNIX password: 
   passwd: all authentication tokens updated successfully.

2. In the home directory of "rsync", create the .ssh folder and the file authorized_keys therein:

   [root@localhost ~]# sudo -H -u rsync mkdir /home/rsync/.ssh
   [root@localhost ~]# sudo -H -u rsync touch /home/rsync/.ssh/authorized_keys
   [root@localhost ~]# chmod 700 /home/rsync/.ssh
   [root@localhost ~]# chmod 600 /home/rsync/.ssh/authorized_keys

3. Next, use your favourite text editor and add the "rsync_tool" SSH key contents seen above in the Ubuntu section to that file. It should be one line and one line only that you add.
4. Prepare the file area where all the mirrored files will live. We'll follow the FHS guidelines , placing the files in /srv/rsync(Rationale: here)

   [root@localhost ~]# mkdir /srv/rsync

5. Next, we'll relabel that folder to let SELinux allow rsync to serve files from that location:

   [root@localhost ~]# chcon -vt public_content_t /srv/rsync
   context of /srv/rsync changed to user_u:object_r:public_content_t

   (Learn more about that using "man rsync_selinux")
6. Create a symbolic link in the home directory of rsync that points to the rsync file area:

   [root@localhost ~]# sudo -H -u rsync ln -sf /srv/rsync /home/rsync/repositories

7. Install the xinetd package (if it isn't already)

   [root@localhost ~]# rpm -q xinetd
   package xinetd is not installed
   [root@localhost ~]# yum install xinetd
   ...
   

8. Configure a new rsyncd service module called "rel". If you haven't got one already, use your favourite text editor to edit or create the file /etc/rsyncd.conf:

   read only = yes
   list = yes
   uid = nobody
   gid = nobody
   
   log file = /var/log/rsync.log
   
   max connections = 25
   
   # This is the six-arma-updater repository, used
   # for the ACE 2 rsync mirror system
   [rel]
       comment = "six-arma-updater rsync repository" 
       path = /srv/rsync/rel
       uid = rsync
       gid = rsync
       read only = yes
   

9. Create the directory "rel" in the rsync file area and make sure the whole file area is owned by the user rsync:

   [root@localhost ~]# mkdir /srv/rsync/rel
   [root@localhost ~]# chown -R rsync:rsync /srv/rsync

10. Enable the xinetd service and rsync sub-service

    [root@localhost ~]# chkconfig rsync on
    [root@localhost ~]# chkconfig xinetd on

11. Open ports 873:TCP and 873:UDP in your firewall. You can do this using the system-config-securitylevel GUI tool. (Advanced users may add new iptables rules to /etc/sysconfig/iptables, but don't call us when you break your firewall - if you aren't sure of what you're doing, don't do it.)
12. Finally, you can start the xinetd service

    [root@localhost ~]# service xinetd start

Limiting bandwidth usage
One way of doing this is by editing the xinetd rsync service configuration file, /etc/xinetd.d/rsync and add --bwlimit=<limit in KiB/sec> to the server_args line. Here's how it may look if you wish to limit the per-connection upload rate to 512 KiB/sec.

# default: off
# description: The rsync server is a good addition to an ftp server, as it \
#       allows crc checksumming etc.
service rsync
{
        disable = no
        socket_type     = stream
        wait            = no
        user            = root
        server          = /usr/bin/rsync
        server_args     = --daemon --bwlimit=512
        log_on_failure  += USERID
}

Note: that's kilo bytes per second, not kilo bits. Once you've edited /etc/xinetd.d/rsync, have the xinetd service re-load the configuration using:

[root@localhost ~]# service xinetd reload

Verification

1. Make sure you can access the rsync service locally. Do this by asking the rsync service to show you a list of the available "modules":

   [root@localhost ~]# rsync localhost::
   rel             "ACE 2 rsync repository"

2. Next, try the same thing from a machine on the outside. This will tell you if you have your firewall setup correctly:

   [user@otherhost: ~]$ rsync myserver.example.com::
   rel             "ACE 2 rsync repository"