Apache's Confusing Access Control

It happens so many times, you write Access Control in Apache by giving "Oder Allow,Deny" or "Order Deny,Allow".

But how would that be executed? I used to check it after applying ACL rules. But now below table will be helpful to evaluate rules.

Example:

	<Location /server-status>
	SetHandler server-status
	Order Allow,Deny
	Deny from 192.168.10.100
	Allow from 192.168.10.0/24
	</Location>

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Looking at above example, we can see that 192.168.10.100 will be denied as per below table.

	Match | Allow,Deny result | Deny,Allow result
	-------------------------------------------------------
	Allow only | Allowed | Allowed
	Deny only | Denied | Denied
	No match | Default: Denied | Default: Allowed
	Match both | Final match: Denied | Final match: Allowed

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Alfresco Cluster Validation

This post would be helpful, if you have setup the Alfresco cluster and found issues(L2 cache replication, Startup error, failed cluster message transmission,etc). Below mentioned points should be taken care before you start testing Cluster in Alfresco.

(1) Make sure the hostname of both Alfresco server are reachable on Resolved IP address.

Ex: you can check with "hostname" command. This command will give you hostname. After that you can try to ping hostname. If you are getting output like "Reply from...", that means hostname is rechable. If you are not getting any other message, then contact system Admin.

(2) Validate Max Open File limit is configured. By default, it is 1024. You can check if Max Open File limit using below command.

First login with the user, by which you are going to start Alfresco. Then run below command.

ulimit -Hn

ulimit -Sn

If you are getting output of above command as "1024" or less. Then modify  /etc/security/limits.conf file and add below lines. Here we are considering that Alfresco is running as "alfresco" user.

alfresco soft nofile 1024

alfresco hard nofile 10240

After you give this command, restart the server. Then check again with ulimit command.

(3) Check if firewall is on or off. If firewall is on in Server, then you may need to open Open ports. Port depends on the setup of Alfresco Custer.

(4) Validate the Java version is Sun JDK.

(5) Validate that the directory in which Alfresco is installed does not contain spaces.

(6) Validate that the directory in which the JVM is installed does not contain spaces.

(7) Validate that the directory Alfresco will use for the repository (typically called alf_data) is both readable and writeable by the operating system user that the Alfresco process will run as.

(8) Validate that you can connect to the database as the Alfresco database user, from the Alfresco server. And you have provided proper library file to connect.

(9) Validate that the character encoding for the Alfresco database is UTF-8. (MySQL only) Validate that the storage engine for the Alfresco database is InnoDB.

(10) If you are using Openoffice then make sure that OpenOffice is able to run in headless mode

Download Oracle JDK using Wget

Downloading Oracle Jdk becomes pain when you want to download it in shell prompt using wget command.
Since oracle does not allow to download oracle jdk without accepting agreement, only wget command will not help you without some other extra switches.

Finally I have found how we can download Oracle JDK in remote server in shell using wget command. Below command can be used to download.

wget --no-cookies --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com" "http://download.oracle.com/otn-pub/java/jdk/6u43-b01/jdk-6u43-linux-i586.bin"

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