guide: installing on CentOS 5
Posted: Sun Dec 02, 2007 4:49 am
This is a guide I have on my site: Guide for Installing Scalix on CentOs 5 with Internal DNS. Since these forums were such a good reference, I think it would be only fair to return that favor. Thank you all!
This is a beginners admin guide / manual, but it still assumes that you would know how to work in a GNU/Linux environment. After all, you ARE installing a server on a GNU/Linux machine, aren't you?
Now, to the guide itself. We will be working on a domain called centos5.com for our examples. There is a real domain by this name, and it is not related to this guide.
Important: almost all network changes can be made through the system-config-network-tui or the system-config-network-gui tools.
Network Basic Settings
The first and most important thing that you need to remember, is to change your machine name to the name of domain that you intend to use. This is done by editing the file /etc/sysconfig/network and changing the HOSTNAME value to your own domain name. I.E., instead of localhost.localdomain you should have centos5.com or whatever domain name that you use. There is a world of trouble that awaits those who fail to remember that.
Secondly, add your domain name to the file /etc/hosts right after the loopback device (I.E., after 127.0.0.1). It should look like this:
You need to replace the 192.168.1.5 to your own local IP address.
Please, oh pretty please: it is best to change your network settings from DHCP to static IP address. This can be done through the setup command. After you make this change, restart the networking services by typing service network restart.
It is advised that after all these steps, you restart your machine. Although there are other ways to apply these changes, it is best that you restart. Besides, you are probably working on a non-production server, otherwise you wouldn't be reading this guide.
Network DNS Settings
This part is for those who wish to have internal domain and IP referrals inside their machines.
What does it mean? Well, it means that before your server starts looking for an external DNS server, it will look at its internal DNS server, and will resolve to the IP addresses that you supply to it.
Edit the file /etc/resolv.conf and add to it the next 1st line:
Edit the file /var/named/chroot/etc/named.conf to make it look this way:
Pay a close attention to the location of the centos5.com.zone file. We will not be using this location, but this the correct line to enter in the file. The reason that we will be using a different location, has to do with default chrooting in the CentOS server. If you didn't understand what I just said, it really doesn't matter.
Now you need to create the following file /var/named/chroot/var/named/centos5.com.zone and this will be our zone file.
The contents of the zone file should look something like this (whatever comes after the ; are comments):
Network Firewall Settings
There is a very easy-to-use tool that comes with CentOS for configuring the firewall. It has 2 versions: the system-config-securitylevel-tui for the textual CLI environment (CLI = Command Line Interface), and the system-config-securitylevel for the graphical environment. These tools are warmly recommended as configuration tools for iptables, with great ease.
Recommended settings:
Security Level: Enabled
SELinux: Disabled
Inside the Customize option of the CLI, and in the Firewall Options tab in the GUI:
Allow incoming: SSH, WWW (HTTP), Secure WWW (HTTPS), Mail (SMTP)
Other ports: 5900:tcp openmail:tcp imap:tcp
Regarding port 5900: this is the default port for VNC connections. Each VNC server receives its own port, so if you plan on opening a server in :3 you will need to open port 5903:tcp instead.
Scalix Installation and Usage
I can not believe that I'm writing this down: do not use the textual installer. Login to your server using VNC, and install Scalix with the graphic installer. The reason is, that the textual installer, for some reason, creates a postgresql problem installing Scalix. In simpler words: the textual installer will not install.
Download the Scalix Community Edition from this link. You need to enter an Email address, and then you are directed to the download page. If you intend to use Scalix with MS Outlook, then this is also where the Outlook Connector is.
Extract the files from the scalix-11.2.0-GA-core-rhel5-intel.tgz file, and from the new scalix-11.2.0-GA folder, activate the following command:
After installing Scalix, go to http://192.168.1.5/sac/ to the administrator console, and setup users and the server.
In http://192.168.1.5/webmail/ you will find the Scalix web interface.
And that's it! You now have an Exchange server, good for 25 Premium users, with a fully functional web access, Calendar sharing, Email and webmail, and all other good stuff.
Enjoy!
Dotan Mazor
This is a beginners admin guide / manual, but it still assumes that you would know how to work in a GNU/Linux environment. After all, you ARE installing a server on a GNU/Linux machine, aren't you?
Now, to the guide itself. We will be working on a domain called centos5.com for our examples. There is a real domain by this name, and it is not related to this guide.
Important: almost all network changes can be made through the system-config-network-tui or the system-config-network-gui tools.
Network Basic Settings
The first and most important thing that you need to remember, is to change your machine name to the name of domain that you intend to use. This is done by editing the file /etc/sysconfig/network and changing the HOSTNAME value to your own domain name. I.E., instead of localhost.localdomain you should have centos5.com or whatever domain name that you use. There is a world of trouble that awaits those who fail to remember that.
Secondly, add your domain name to the file /etc/hosts right after the loopback device (I.E., after 127.0.0.1). It should look like this:
Code: Select all
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
192.168.1.5 centos5.com centos5
You need to replace the 192.168.1.5 to your own local IP address.
Please, oh pretty please: it is best to change your network settings from DHCP to static IP address. This can be done through the setup command. After you make this change, restart the networking services by typing service network restart.
It is advised that after all these steps, you restart your machine. Although there are other ways to apply these changes, it is best that you restart. Besides, you are probably working on a non-production server, otherwise you wouldn't be reading this guide.
Network DNS Settings
This part is for those who wish to have internal domain and IP referrals inside their machines.
What does it mean? Well, it means that before your server starts looking for an external DNS server, it will look at its internal DNS server, and will resolve to the IP addresses that you supply to it.
Edit the file /etc/resolv.conf and add to it the next 1st line:
Code: Select all
nameserver 192.168.1.5
Edit the file /var/named/chroot/etc/named.conf to make it look this way:
Code: Select all
zone "centos5.com" {
type master;
file "/var/named/centos5.com.zone";
};
Pay a close attention to the location of the centos5.com.zone file. We will not be using this location, but this the correct line to enter in the file. The reason that we will be using a different location, has to do with default chrooting in the CentOS server. If you didn't understand what I just said, it really doesn't matter.
Now you need to create the following file /var/named/chroot/var/named/centos5.com.zone and this will be our zone file.
The contents of the zone file should look something like this (whatever comes after the ; are comments):
Code: Select all
$ORIGIN centos5.com.
$TTL 86400
@ IN SOA centos5.com. administrator.centos5.com. (
2001062501 ; serial
518400 ; refresh after 6 days
3600 ; retry after 1 hour
604800 ; expire after 1 week
86400 ) ; minimum TTL of 1 day
IN NS centos5.com.
IN MX 10 mail.centos5.com. ; this is the line for the mail MX records
IN A 192.168.1.5
server1 IN A 192.168.1.5
server2 IN A 192.168.1.22
ftp IN CNAME server2 ; this will cause ftp.centos5.com to resolve go to 192.168.1.22
mail IN CNAME server1 ; this will cause mail.centos5.com to resolve to 192.168.1.5
www IN CNAME server1 ; this will cause www.centos5.com to resolve to 192.168.1.5
Network Firewall Settings
There is a very easy-to-use tool that comes with CentOS for configuring the firewall. It has 2 versions: the system-config-securitylevel-tui for the textual CLI environment (CLI = Command Line Interface), and the system-config-securitylevel for the graphical environment. These tools are warmly recommended as configuration tools for iptables, with great ease.
Recommended settings:
Security Level: Enabled
SELinux: Disabled
Inside the Customize option of the CLI, and in the Firewall Options tab in the GUI:
Allow incoming: SSH, WWW (HTTP), Secure WWW (HTTPS), Mail (SMTP)
Other ports: 5900:tcp openmail:tcp imap:tcp
Regarding port 5900: this is the default port for VNC connections. Each VNC server receives its own port, so if you plan on opening a server in :3 you will need to open port 5903:tcp instead.
Scalix Installation and Usage
I can not believe that I'm writing this down: do not use the textual installer. Login to your server using VNC, and install Scalix with the graphic installer. The reason is, that the textual installer, for some reason, creates a postgresql problem installing Scalix. In simpler words: the textual installer will not install.
Download the Scalix Community Edition from this link. You need to enter an Email address, and then you are directed to the download page. If you intend to use Scalix with MS Outlook, then this is also where the Outlook Connector is.
Extract the files from the scalix-11.2.0-GA-core-rhel5-intel.tgz file, and from the new scalix-11.2.0-GA folder, activate the following command:
Code: Select all
./scalix-installer --override=rhel5
After installing Scalix, go to http://192.168.1.5/sac/ to the administrator console, and setup users and the server.
In http://192.168.1.5/webmail/ you will find the Scalix web interface.
And that's it! You now have an Exchange server, good for 25 Premium users, with a fully functional web access, Calendar sharing, Email and webmail, and all other good stuff.
Enjoy!
Dotan Mazor
I've done several Scalix installations on CentOS 5, always used the textual installer (I don't want a graphical environment on a server!) and it always worked fine for me.