VICOSYS

Adding Sender Blacklist in Forefront for Exchange 2007

June 30th, 2010

To add a sender blocking list to Exchange 2007 protected by Forefront, you will need to perform the following actions under “Exchange Management Console”

– Open Organization Configuration
– Hub Transport
– Anti-spam
– Sender Filtering
– Properties
– Add the email address or the domain you want to block.

Posted in Email, Exchange | No Comments »

Data Center Tiering

June 9th, 2010

When we evaluate datacenter quality, often time, we will look at datacenter tiering. Below is the table describes various Datacenter Tiers.

Tier 1 –
Has non-redundant capacity components and a single, non-redundant distribution path serving the computer equipment

Tier 2 –
Has redundant capacity components and a single, non-redundant distribution path serving the computer equipment.

Tier 3 –
(a) Has redundant capacity components and multiple independent distribution paths serving the computer equipment. Only one distribution path is required to serve the computer equipment at any time.
(b) All IT equipment is dual powered and installed properly to be compatible with the topology of the site’s architecture.

Tier 4 –
(a) Has multiple, independent, physically isolated systems that provide redundant capacity components and multiple, independent, diverse, active distribution paths simultaneously serving the computer equipment.
(b) All IT equipment is dual powered and installed properly to be compatible with the topology of the site’s architecture.
(c) Complementary systems and distribution paths must be physically isolated from one another (compartmentalized) to prevent any single event from simultaneously impacting both systems or distribution paths.
(d) Continuous cooling is required.

Posted in Networking | No Comments »

Running OSX on VMWare Fusion

June 7th, 2010

The following steps describe how you can install OS X on VMware Fusion.

sudo su –
cd “/Library/Application Support/VMware Fusion/isoimages”
mkdir original
mv *.sig original
mv darwin.iso original
sed “s/ServerVersion.plist/SystemVersion.plist/g” < original/darwin.iso > darwin.iso
openssl genrsa -out tools-priv.pem 2048
openssl rsa -in tools-priv.pem -pubout -pubout -out tools-key.pub
openssl dgst -sha1 -sign tools-priv.pem < darwin.iso > darwin.iso.sig
for A in *.iso ; do openssl dgst -sha1 -sign tools-priv.pem < $A > $A.sig ; done
exit

Posted in OSX | No Comments »

Loading a Text File Line by Line in a Bash Shell

May 13th, 2010

The following example demonstrates how to load a text file into array in a Bash Shell.

#!/bin/sh count=0 while read line do ARR[$count]=$line ((count++)) done < /tmp/infile for LINE in ${ARR[*]} do echo $LINE done

Posted in Bash, Linux | No Comments »

Create an Apache Self-signed Certificate without a PassPhrase

April 3rd, 2010

This is annoying to start the apache webserver with SSL. After hours of research, I found the following procedures can create a certificate that does not require to type passphrase.

It could be less secured – so use it at your own risk!!

This is how we can generate a DSA Certificate without a passphrase.

openssl dsaparam 1024 -out dsaparams
openssl gendsa -out ca.key dsaparams
openssl req -new -key ca.key -out ca.csr
openssl x509 -req -days 365 -in ca.csr -signkey ca.key -out ca.crt

Posted in Apache | No Comments »

Auto close a SSH session after a period of idle activities

January 26th, 2010

to automatically close a SSH connection on the server, we can change the following ssh configuration.

Edit /etc/ssh/sshd_config

Change
ClientAliveInterval 300
ClientAliveCountMax 3

service sshd restart

Posted in Linux | Comments Closed

Javascript to convert Simplified and Traditional Chinese

August 31st, 2009

http://blog.markplace.net/marks_place/10/2006/10/27/150

download tw_cn.js

Posted in javascript, Joomla | Comments Closed

Mounting filesystem with noatime to improve performance

August 30th, 2009

atime is to record the last access time of a file in a Linux Filesystem. In a busy system, this could be a heavy tax in a busy system. People reported 5% to 20% performance gain bbut your milage may varies.

To disable the record of the atime.

vi /etc/fstab
/dev/VolGroup00/LogVol04 /usr/local/mysql/var ext3 rw,noatime 1 2

Remount the filesystem to take effect of the update
mount -o remount /usr/local/mysql/var

Check the mount options
[root@mail01a ~]# mount
/dev/mapper/VolGroup00-LogVol00 on / type ext3 (rw)
/dev/mapper/VolGroup00-LogVol05 on /home type ext3 (rw)
/dev/mapper/VolGroup00-LogVol03 on /usr type ext3 (rw)
/dev/mapper/VolGroup00-LogVol04 on /usr/local/mysql/var type ext3 (rw,noatime)
/dev/mapper/VolGroup00-LogVol02 on /var type ext3 (rw)

Posted in Linux | Comments Closed

Redirecting a website based on source IP address.

July 6th, 2009

To use .htaccess to redirect a website based on the source ip address.

RewriteEngine on
RewriteCond %{REMOTE_HOST} 192.168.1 [OR]
RewriteCond %{REMOTE_HOST} 172.16
RewriteRule “^(.*)$” “http://www2.domainname.com/$1” [R=301,L]

Posted in Apache | Comments Closed

Importing a Table with Duplicate Rows and Unique Index

June 27th, 2009

When you import a table with Unique key index and contains duplicated rows, you can use the following steps to get around the error.

#1062 – Duplicate entry ‘xxxxxxx’ for key 1

1. Drop the Unique Index on the table.
ALTER TABLE table_name DROP INDEX index_name

2. Import data

3. Create the Unique Index
ALTER IGNORE TABLE `table_name` ADD UNIQUE INDEX `index_name` (`column_name`);

Posted in MySQL | Comments Closed