bytes off, baby

Yet another fast (online!) Java decompiler

2012-01-25T23:08:00.000-08:00

Being lazy to setup jad on each machine I just found the solution - Java Decompiler with do-it-online feature! Another cons - beside core lib it has version with UI.
Happy hacking, brothers!

IntelliJ IDEA: Clear pending incoming changes

2011-02-24T00:48:00.000-08:00

Sometimes my IDEA goes crazy - it shows available incoming changes though all project files are up-to-date. In particular, I use IntelliJ IDEA 9.04 and SVN.

Fix is rough and effective - just clean up IntelliJ IDEA vcs (version control system) cache: delete directories
[user home dir]/.IntelliJIdea90/system/vcs
[user home dir]/.IntelliJIdea90/system/vcsCache

Most wanted Maven commands

2011-02-16T09:06:00.000-08:00

... which I used to forget!

Generate Eclipse project file(s) for your (built with Maven) project
```
cd [project root dir]
mvn eclipse:clean eclipse:eclipse
```
Build project quickly: don't check if there are updated artifacts (i.e., offline mode) and don't run tests
```
cd [project root dir]
mvn clean install -o -DskipTests
```

Run main() method of your java class

mvn exec:java -Dexec.mainClass="com.example.Main" [-Dexec.args="argument1"]

Build a project module and all modules it depends on

cd [project root dir]
mvn clean install -pl [relative path from current dir to module you want to build] -am

Continue to build a project from the module on which previous build procedure has been interrupted (for example, because of build failure)

cd [project root dir]
mvn clean install -rf [relative path from current dir to module on which previous build procedure has been interrupted]

Run specific goal for a given plugin

mvn [plugin groupId]:[plugin artifactId]:[specific goal]

Initialize new project in maven way
```
mvn archetype:generate
```

Questions on Java interview

2010-12-29T02:22:00.000-08:00

Guys, I'd like to share with the (big) world my modest Java interviewing experience. Here are the questions which I pester job-candidates with:

Object Oriented Programming

Central idea of Object Oriented Programming in one sentence
Central idea of Structured Programming in one sentence

Core Java

Multiple inheritance in Java (classes and interfaces)
What are the differences between Interface and Abstract Class?
What final classes in Java SDK you know? Why they are declared final?
What are the (non-) final methods of Object class? Why?
How to override Object.clone() method correctly?
Collections
- What is the difference between ArrayList and Vector?
- How to sort a collection of your own classes?
- [Senior] What sorting algorithm is used in Collections.sort()? Why?
- How to filter out (i.e., remove some items) from ArrayList while iterating through it?
Exceptions
- Types and the difference
- What kind of exception can you catch?
- Is it safe to catch Throwable?
Threads
- What are the static and instance methods in a Thread class?
- Why static methods in a Thread class are static and instance method are not?
- What is the difference between Thread.sleep() and someObject.wait() methods?
- What are the immutable objects? When to use?
- [Senior] What are the reasons to use utils in the package java.util.concurrency?
- [Senior] What is a ThreadLocal? How you can use it in production code?
Serialization
- How to make a class serializable?
- Java IDEs shows us warning if the serializable class doesn't declare static final field of type long, "serialVersionUID". Why to worry?
Quirks
- Is it possible to have two object of the given singleton class in one VM? If so - then how?

Enterprise Java

Servlets: when servlet is instantiated?
Servlets: how much servlet' instances of a same class simultaneously live in servlet container?
Are servlets thread-safe?

Object-relational mapping

What are the requirements for the Entity?
Is it necessary to override Entity.equals()? How to implement Entity.equals()? What are the caveats?
What is lazy loading? Is it dangerous?

Simple algorithms

Transform given string "Bob doesn't eat dogs" to the new one "dogs eat doesn't Bob". String.split() usage is prohibited.
Bubble sorting. Algorithm improvements.

"Mmmmmmmm...." questions

What a new trick/feature you'd found in Java?
Which software pattern you are using most? Why?
Why Multiple inheritance is bad?
What is the latest IT technology you'd discovered for yourself?
Which IT achievement you can be proud of?

Ideas for pair programming session

Bubble sorting. Unit tests and algorithm improvements
Modelling computer network. Instances: domains, subdomains, hosts. Operations:add, delete, move, find. Unit tests.
Echo server and client.
Modelling animal farm. Instances: pig, cat, dog. Operations: create, feed, sound. Unit tests.
Modelling computer network. Instances: domains, subdomains, hosts, settings (collection of key-value pairs). Operations: apply setting to host/domain, override set of parameters on host/domain. Unit tests.
Modelling computer network. Instances: domains, subdomains, hosts. Operations: sort hosts according to their nesting(starting from root).

Data synchronization design pattern

2010-12-24T06:08:00.001-08:00

Data synchronization, incremental/bulk updates.. We all know these problematic words but who knows that the restless human mind has already systematized this field?
Lady and gentlemen, let me introduce Change data capture design pattern.

Wikipedia says:
Change data capture (CDC) is a set of software design patterns used to determine (and track) the data that has changed so that action can be taken using the changed data. Also, Change data capture (CDC) is an approach to data integration that is based on the identification, capture and delivery of the changes made to enterprise data sources.

You won't find any concrete class diagram in CDC pattern. But definitely will get some ideas and best-practices of data sync implementation.

Debug SSL-TLS connections in java application

2010-12-20T01:04:00.001-08:00

I'd lust SSL debugging vastly.. And what?!

I'd found this feature not in third-party libs, sniffer applications, firewalls, etc. The miracle was in ~~my trunks~~ JRE!
Java Secure Socket Extension (JSSE) do provides dynamic debug tracing support.
JVM parameter -Djavax.net.debug with these options is a magic wand:

all turn on all debugging
ssl turn on ssl debugging

The following can be used with ssl:

record enable per-record tracing
handshake print each handshake message
keygen print key generation data
sessionprint session activity
defaultctx print default SSL initialization
sslctx print SSLContext tracing
sessioncache print session cache tracing
keymanager print key manager tracing
trustmanager print trust manager tracing

handshake debugging can be widened with:

data hex dump of each handshake message
verbose verbose handshake message printing

record debugging can be widened with:

plaintext hex dump of record plaintext
packet print raw SSL/TLS packets

Run this and you'll see everything:

java -Djavax.net.debug=all MyApp

All the stuff for this post has been frankly stolen from here. And real nerds would be interested in detailed SSL/TLS debugging.

P.S.
SSL debug utility is not an officially supported feature of JSSE..

Puttycyg - the best console for Cygwin

2010-02-24T03:37:00.001-08:00

I tried many home-grown projects just to feed a lust for a simply.. good console in Windows. And for sure, cmd.exe is out of comments. I had a wish - putty + Cygwin but I'm too lazy to do it myself. Happily, someone (medgar123) done it - puttycyg is a place for heaven.

Here is a small screen shot.

NUL character in Windows clipboard

2010-01-28T23:42:00.000-08:00

Recently I'd failed to copy/paste simple text block with text editor SciTE - I was able to copy (and paste) only a part of selected text block. Well, I've cowardly thought that the time has come to leave an old good friend and migrate to proven Notepad++. No sooner said than done. And.. the famous Notepad++ couldn't copy the same text block also! Googling help me, I thought and started.

Firstly, I found out that Notepad uses SciTE component (at-least) for the copy-paste. Then I went deeper and realized that text block which is finally pasted stops on the symbol NUL, i.e., I was able to copy everything up to the first NUL occurrence. And again, Google gave me an answer - this is another one funny Windows limitation. Text with NUL character can't be copy/pasted in Windows.
But it was really necessary to copy that text! The only way I found was to make Notepad++ interpret NUL characters as white spaces and then - do copy/paste.
I also tried to use a native notepad.exe to open the problematic document - and again, Windows played the worst - NUL character were not shown as NUL, they were automatically transformed to white spaces. As you may guess, copy/pasting of text block with white spaces is affordable even for notepad.exe.

P.S.
NUL character in Notepad++.

Look out, you naive copy-pasters!

How to avoid java applet caching

2010-01-18T03:47:00.000-08:00

If you ever faced with Java applet development you've already noticed annoying caching. Applets could be cached almost everywhere - even on your HTTP proxy. The only real way to clean up cached java applets that I know is:

Turn of proxy usage in web browser
Clean up browser cache
Close any java program
Delete java cache from the computer you work on: for example, on Windows, remove directory
```
%Documents and Settings%\%your_user_name%\Application Data\Sun\Java\Deployment
```
If the step 3 haven't been executed you may not be able to delete this directory.

ClearCase: customize associatiions operation - tool

2010-01-14T07:14:00.000-08:00

I dislike some (to be honest, many of) standard ClearCase tools, for example, xml-files compare tool and file-merge tool. Even more, I already have my lovely tools for everything. The deal is - how to make ClearCase use my custom soft instead of the bundled tools?

And the answer is: there is a special ClearCase file which maps file extension, source control function and the tool to execute this function. Map-file can be found here:

INSTALLED_CLEARCASE_DIR/lib/mgr/map

On my Windows dev PC the path is C:\Program Files\Rational\ClearCase\lib\mgrs\map.

ClearCase: how to get view private files

2009-11-19T07:23:00.000-08:00

One of the needed features which is not accessible via ClearCase GUI is: how to get the list of files that are located in a view but not under source control.
The the answer is
for the dynamic views:

cleartool lsprivate

and for the snapshot views:

cleartool ls -recurse -view_only

Linux: runing app in daemon/background mode

2009-11-17T01:36:00.000-08:00

Every cool guy knows that launching command with ampersand ('&') at the end leads to the background (let's say, console non-blocking) command processing. For sure, we talk about the honest Linux world. Meanwhile, there is a task which is widely used in a day-to-day IT life:

log in to a Linux server via ssh
launch some application, script which 1) is not designed as a daemon, 2) produces output to std out/ std error:
```
./myApp.sh &
```
log off from the server.

But when you are trying to access your server-side application you've got it stopped! Why?

You do remember that you've launched it with the ampersand at the end. The answers - below.
First of all, if your application provides any data to the std out or std error streams then you have to redirect those outputs somewhere, for example, to a log file, or to /dev/null if the output won't be taken into account.

./myApp.sh &> log.txt &

Here we've done redirect of both system out and system error streams to the file 'log.txt'. Redirect should be done to detach your app from console which will be destructed upon the logout.
But it not enough to fix our problem: launched command should live after our logout.
And here nohup goes on:

nohup sh myApp.sh &> log.txt &

That's it! When you do logout the sshd application which hosted your appearance on the server is killed so the same signal is sent to each child process of the sshd - even for the 'myApp.sh'. You may run pstree on the server to check real process tree. Nohup makes your application immune to the hangup signal, qoute from man page: "so that the command can continue running in the background after you log out". It should be stated that with nohup it is not necessary to tun application in background mode.

nohup sh myApp.sh &> log.txt

It's just a matter of console - it won't be blocked if application has been run with ampersand.

There is another one useful and mature program called screen which gives you more opportunities but this another long story to tell. You'll easily find info with "screen linux" request to any search engine.

How to determine process id of java application

2009-11-03T09:47:00.000-08:00

There is a classic task - stop or restart some java application on the server where several java apps are running. Common solution is to use "ps" on Linux or Process Explorer on Windows. But there is another one, more handy and useful option: use jps command which is bundled in JDKthe JAVA_HOME/bin:
I prefer to do it this way:

jps -mlv | grep some_text_to_identify_app

Here output of 'jps -mlv' on my Windows PC:
4452 -Dosgi.requiredJavaVersion=1.5 -Xms40m -Xmx512m -XX:MaxPermSize=256m
2060 org.apache.catalina.startup.Bootstrap start -agentlib:jdwp=transport=dt_socket,suspend=y,address=localhost:4414 -Dcatalina.home=D:\programs\java_
stuff\apache-tomcat-6.0.18 -Djava.endorsed.dirs=D:\programs\java_stuff\apache-tomcat-6.0.18\endorsed -Dcatalina.base=D:\programs\java_stuff\apache-tom
cat-6.0.18 -Djava.io.tmpdir=D:\programs\java_stuff\apache-tomcat-6.0.18\temp -Dfile.encoding=UTF-8
4532 sun.tools.jps.Jps -mlv -Dapplication.home=D:\programs\java_stuff\Java\jdk1.6.0_13 -Xms8m

Java: BufferedReader and reading line-by-line

2009-10-26T07:29:00.000-07:00

It's common way to use buffered wrapper - java.io.BufferedReader - for the file/network/etc read operations. And one of the most useful features: readLine() method. What it returns? Javadoc answers:

"A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached". Folks! Pay attention on that "null"! Wanna arguments? Have a real-life examples:

1. HOW-TO-DO: correct way to read input data

BufferedReader reader;
//...
String line;
while ((line = reader.readLine()) != null) {
  //do something
}

Major point in this example is a null-checking, i.e., we should not only read data but also check if the wrapped stream hasn't been closed.

2. HOW-NOT-TO-DO: incorrect way to parse some text from read input data

BufferedReader reader;
//...
String line;
while (true) {
  line = reader.readLine());
  if ((line == null)) || !line.isEmpty()) {
    // All input data has been read so let's analyze it
    analyzeBunchOfData();
  }
}

What's wrong here? That old ugly null returned by BufferedReader. Here we assume that if nothing (null) has been read - than some bunch of input data has come. But it is no so! Again, if BufferedReader returns null - it means that internal stream has been closed, that, in turn, in most cases means that input resource has been closed, for example, network connection has been closed on the other side.

The moral

Be accurate when you work with low-level input/output operations. At least.

Multiple genre tags support in Foobar 2000

2009-10-22T00:28:00.000-07:00

Philosophical intro: "Named means exist".
I use Foobar 2000 as a music player. Recently I've found how to make Foobar apply and visualize in "Album List" multiply genre tags. Simply use semicolon ";" to separate values!

Here is my "demo":

How to mount disk to specific drive letter

2009-10-20T05:21:00.001-07:00

The problem
Pre: for sure, we'll talk about lovely Windows cause in Linux even the meaning of the word "problem" differs..
So, you have a removable disk (flash or hard drive) and when you plug it into your Windows PC it appears with different drive letters. For example, you have a bunch of media on a flash drive. You plug it for the first time, Windows provides drive letter "G" for this drive. Then you import all media into some media library. After a while you pull out flash and later plug it again. Now Windows decides to name this drive letter with "F" and.. you can't access your media files from the media library. On my own PC this happens not so frequently but each time I have to refresh my media library in Foobar 2000 player. So boring!
The day has come to say "NO"!

The solution
I've done simple script which automatically mounts disk to the drive letter you want to. I dislike writing tricky bat-files, and I also wondering in Groovy, that it to say, my auto-mount feature requires Java and Groovy installed. You can read a small how-to-configure-environment-guide. The script below should be run after the needed disk has been plugged, i.e., after the Windows has mounted the disk. Another requirement is to pre-define disk label.

def NEEDED_DRIVE_LETTER = 'B'
def DISK_LABEL_TO_SEARCH = 'STORAGE'


def txt = 'cmd /c mountvol'.execute().text
def m = []
txt.split('[\\r\\n]+').each {m << it.trim()}

def volumeId
def disk
m.eachWithIndex() { obj, i -> 
  if (obj.endsWith(':\\')) {
    txt = "cmd /c vol ${obj - '\\'}".execute().text
    if (txt.contains(" is $DISK_LABEL_TO_SEARCH")) {
      volumeId = m[i - 1]
      disk = obj
    }
  }
}


if (!(NEEDED_DRIVE_LETTER + ':\\').equalsIgnoreCase(disk)) {
  "cmd /c mountvol $disk /d".execute()
  "cmd /c mountvol $NEEDED_DRIVE_LETTER: $volumeId".execute()
}

Two points to customize in this script are right are:
NEEDED_DRIVE_LETTER - drive letter where you want to mount your disk
DISK_LABEL_TO_SEARCH - disk label of your disk

P.S. Please don't blame my groovy karma - I'm a youngster in this field. Anyway, every comment is welcome!

Save all opened tabs in Firefox

2009-07-06T23:45:00.000-07:00

Historically some of us don't trust Firefox to store all opened tabs on close - Tab mix plus addon was one of mine favorites.. But from version_3_God's_know_what_exactly Firefox has native/default mechanism to save tabs. What is interesting- my PRO (developers and sys admins) friends/colleagues don't know how to activate Firefox tabs saver but other NORMAL people do know. This is for you, my lovely geeks:

Open Firefox -> Tools -> Options -> Main -> Startup
Set When Firefox starts: Show my windows and tabs from the last time

Hudson plugin for Eclipse

2009-07-01T07:02:00.000-07:00

You code in Eclipse and use Hudson for the continuous integration? You are lazy enough to use great (really) Hudson web interface? Then you need a hudson-eclipse plugin! With hudson-eclipse you are able to monitor project build status, schedule new build and view console output right in your favorite IDE.

One note to mention: if your Eclipse is configured to use proxy for internet connections and your build-server is in the local network then you may experience some troubles during plugin configuration. Just add build-server address to the bypass list (Eclipse -> Window -> Preferences -> General -> Network Connections -> No proxy for).

Fix spell cheking in MS Outlook 2007

2009-07-01T02:13:00.000-07:00

Problem
You had installed MS Office 2007 and now you find out that spell cheeking doesn't work in MS Outlook, but works in MS Word. Welcome to the planet MS!

Fix

Delete (or rename) registry key

HKEY_CURRENT_USER\Software\Microsoft\Shared Tools\Proofing Tools\1.0\Override

Restart Outlook

Prevent Mylyn auto add new files in context

2009-06-30T03:43:00.000-07:00

Problem
I'm using Eclipse Mylyn plugin to be more task-oriented (ha-ha). By default Mylyn auto add new *.java, *. xml (and many other) files (that may not be interesting to you) to the context of the active task. For example, you work in a team on your own particular task, i.e. editing 5 files. And youl collegue commit 50 new files. You update the project and- you've got 55 files in task context but 50 of them absolutely not relative to your current job. In task context I want to see ONLY those files that have been opened by myself.

Fix
Stop Mylyn to monitor new resources!

Eclipse -> Window -> Preferences -> Tasks -> Resources -> Resource Monitor Exclusion
Click on "Add" and provide patterns for the files. " I want to exclude all so the only pattern I have is "*".

Remarks
All above is actual for the Eclipse 3.4 and Mylyn 3.2, but I guess for other version behavior would be the same.

Pimp your Outlook messaging

2009-06-17T06:02:00.000-07:00

Outlook is so common rich application.. but it lacks of some simple and so much needed functions like:

Edit message as new
New message with already filled CC
Reply to message with already filled CC

But real cool hackers never give up even if your best friend name is Bill.

Let's do it.

Pre-requests

MS Outlook 2003/2007
Patience (you've mentioned 'MS' in the point one, ain't so?)

All said below is tested on the MS Outlook 2003 and MS Outlook 2007, screenshots were done with the Outlook 2007.

Outlook and VBA macros
We start with the "Edit message as new" feature. "Edit as new" is a must-have when you want simply re-send message to somebody (not to forward, or to reply) or when you need to make some changes to message you'd sent earlier and re-send again. For sure, there is a standard function in Outlook for this: double click on some message -> click on the "Other Actions" item in toolbar -> choose "Edit message" in drop-down list. But we are lazy enough, we wish to do this with one click! So:

Open Outlook
Tools -> Macro -> Visual Basic Editor (or simply press ALT+F11)
In the opened editor you'll see project structure on the left. Expand it: Project1 -> Microsoft Office Outlook Objects -> double click on node ThisOutlookSession.

Paste the code below to the opened editor

Sub EditAsNew()
Dim msg As Outlook.MailItem
Set msg = Outlook.ActiveExplorer.Selection(1)
If msg Is Nothing Then Exit Sub
If Not TypeOf msg Is Outlook.MailItem Then Exit Sub

Dim newMsg As Outlook.MailItem
Set newMsg = Application.CreateItem(olMailItem)
newMsg.To = msg.To
newMsg.CC = msg.CC
newMsg.BCC = msg.BCC
newMsg.Subject = msg.Subject
Call copyAttachments(msg, newMsg)
newMsg.Body = msg.Body
newMsg.Display

Set msg = Nothing
Set newMsg = Nothing
End Sub

Sub copyAttachments(objSourceItem, objTargetItem)
Set fso = CreateObject("Scripting.FileSystemObject")
Set fldTemp = fso.GetSpecialFolder(2) ' TemporaryFolder
strPath = fldTemp.Path & "\"
For Each objAtt In objSourceItem.Attachments
strFile = strPath & objAtt.FileName
objAtt.SaveAsFile strFile
objTargetItem.Attachments.Add strFile, , , objAtt.DisplayName
fso.DeleteFile strFile
Next

Set fldTemp = Nothing
Set fso = Nothing
End Sub

Save (CTRL+S) and close Visual Baic Editor
Lets check! Select some message from 'Sent' folder and press ALT+F8
You'll probably see Outlook message "Microsoft Office has identified a potential security concern"
In opened window with list of available macroses choose our 'EditAsNew' and run it (button "Run")
You should see chosen message ready to be edited and re-send

Well, it works (at least - on my side). But life is too shot to accomplish items 5 and 7 each time you want to re-send message. That's why you'll read next chapter - Outlook tuning.

Outlook tuning
I know 3 methods to make world go around: keyboard, mouse and "Mu-u-u-m! Please, ...". It is possible to use shortcuts to launch macroses and I'm going to show how to do this in the next post.
But now, mouse-users, unite! We are going to customize Outlook toolbar- remove rarely used items and add our hand-made beauties.

Right-click on standard toolbar

and choose "Customize"
Click on any unwanted item from the standard toolbar and drag it somewhere out if toolbar - you'll see dagger - drop the item and it will disappear from the toolbar
You've finished him/them? Let's add new button to launch "EditAsNew" macros. Recall (if needed) menu "Customize" (see step 1) -> tab Commands -> Categories: Macros -> Select macros "EditAsNew"
Drag macros "EditAsNew" to the the toolbar and place it where you like. You'll get something like this:
Do you like this informative caption for our new button? Me- not. But this is Outlook and everything is possible tonight. Let's rename caption: menu "Customize" (step 1 again) -> tab Commands -> Rearrange commands -> Choose a menu or toolbar to rearrange: Toolbar Standard -> select naughty "Project1.ThisOutlookSession.EditAsNew"
Click to Modify Selection and change field "Name" in drop-down menu to whatever you like. As for me - straight "EditAsNew" is well enough.

That's all! The road wasn't easy and paved with yellow bricks but.. we just made MS Outlook more user-oriented - quite a lot for a mere mortals!

The rest
As you might remember, at the beginning we were talking also about such features as

New message with already filled CC
Reply to message with already filled CC
Reply to all with already filled CC

A bit of explanations: imagine you are THE BIG BOSS. For sure you have pretty nice secretary and one of her duties (one of, I said) is to be up on everything about your day plan. Each time you send (or reply to) e-mail concerning to your business meets- you have to put Her (that secretary, aha) in CC. You are still doing so? We are coming to you then!
To add these features you need:

VBA code for macroses (see below). Don't forget to modify the code - change e-mail from "prettysec@myrichoffice.com" to the correct one
Run through the steps described above in a chapters "Outlook and VBA macros" and "Outlook tuning". NOTE: macroses should be pasted to the VBA editor, one after one.

MS Outlook and "New message with already filled CC"

Sub NewWithCc()
Dim msg As Outlook.MailItem
Set msg = Application.CreateItem(olMailItem)
msg.CC = "prettysec@myrichoffice.com"
msg.Display

Set msg = Nothing
End Sub

MS Outlook and "Reply to message with already filled CC" feature

Sub ReplyWithCc()
Dim msg As Outlook.MailItem
Set msg = Outlook.ActiveExplorer.Selection(1)
If msg Is Nothing Then Exit Sub
If Not TypeOf msg Is Outlook.MailItem Then Exit Sub

Dim reply As Outlook.MailItem
Set reply = msg.reply
reply.Display
reply.CC = "prettysec@myrichoffice.com"

Set msg = Nothing
Set reply = Nothing
End Sub

MS Outlook and "Reply to all with already filled CC" feature

Sub ReplyToAllWithCc()
Dim msg As Outlook.MailItem
Set msg = Outlook.ActiveExplorer.Selection(1)
If msg Is Nothing Then Exit Sub
If Not TypeOf msg Is Outlook.MailItem Then Exit Sub

Dim reply As Outlook.MailItem
Set reply = msg.ReplyAll
reply.Display
reply.CC = msg.CC + "; prettysec@myrichoffice.com"

Set msg = Nothing
Set reply = Nothing
End Sub

The last
My real Outlook standard toolbar screenshot. Check it out!

Time synchronizing in VmWare virtual machine

2009-06-10T07:31:00.000-07:00

I just found fundamental manual - Timekeeping in VMware Virtual Machines. Main idea:

If you want to have "real" time on your virtual machine and don't want to pay much for this (won't you install those famous VmWare Tools?) and your virtual OS is:

Windows... Well, brother, fight for yourself.. (anyway, mentioned super-mega-manual would be definitely helpful)
Linux. [a certain Torvalds will smirk]. Here I is a big fat quote that really rocks.

QUOTE_START

The Network Time Protocol is usable in a virtual machine with proper configuration of the NTP daemon. The following points are important:

Do not configure the virtual machine to synchronize to its own (virtual) hardware clock, not even as afallback with a high stratum number. Some sample ntpd.conf files contain a section specifying the local clock as a potential time server, often marked with the comment “undisciplined local clock.” Delete anysuch server specification from your ntpd.conf file.
Include the option tinker panic 0 at the top of your ntp.conf file. By default, the NTP daemonsometimes panics and exits if the underlying clock appears to be behaving erratically. This option causesthe daemon to keep running instead of panicking.
Follow standard best practices for NTP: Choose a set of servers to synchronize to that have accurate time and adequate redundancy. If you have many virtual or physical client machines to synchronize, set upsome internal servers for them to use, so that all your clients are not directly accessing an external low‐stratum NTP server and overloading it with requests.

The following sample ntp.conf file is suitable if you have few enough clients that it makes sense for them to access an external NTP server directly. If you have many clients, adapt this file by changing the server names to reference your internal NTP servers.
NOTE Any tinker commands used must appear first.

# ntpd.conf
tinker panic 0
restrict 127.0.0.1
restrict default kod nomodify notrap
server 0.vmware.pool.ntp.org
server 1.vmware.pool.ntp.org
server 2.vmware.pool.ntp.org
server 3.vmware.pool.ntp.org

Here is a sample /etc/ntp/step-tickers corresponding to the sample ntp.conf file above.

# step-tickers
0.vmware.pool.ntp.org
1.vmware.pool.ntp.org

Make sure that ntpd is configured to start at boot time. On some distributions this can be accomplished with the command chkconfig ntpd on, but consult your distribution’s documentation for details. On most distributions, you can start ntpd manually with the command /etc/init.d/ntpd start.

QUOTE_END

Youtube engine revealed!

2009-06-10T02:32:00.000-07:00

Now I know the God's phone, yet not a number but the model of.
My friend sent me this:

Great and ugly Google uses Apache server for the youtube service.
Well, why not?

How to register VmWare ESXi server

2009-06-05T04:44:00.000-07:00

Everyone know that VmWare ESXi server is free of charge but few of us knows where to get license key and how to apply it. Read this and you'll be the one who CAN.

First of all, license key is provided on the official VmWare site when you start ESXi downloading.

Next, to accomplish registration you need:

Install VmWare ESXi
Login to ESXi with the VMware Infrastructure Client
(you may download it from the http://<your_vmware_esxi_ip>)
Go to section Inventionary -> tab Configuration -> Software -> Licensed Features -> License Source
In opened window check Use serial number and put the number you got there

Trivial, huh?

RHEL 5 and samba/windows share resources

2009-05-28T07:20:00.000-07:00

"Everything changes"..
From Red Hat, version 5, you need to use 'cifs' fyle system type instead 'smbfs' to mount samba/windows share resources.

Example:


mount -t cifs -o username=mydomain/myuser //172.17.1.1/public /mnt/share/

Hold/mute with FreeSwitch and Asterisk

2009-05-28T04:17:00.000-07:00

Now I know how the "hold" and "mute" works on FreeSwitch and Asterisk (in a lure of SIP). X-Lite, Eyabeam and SjPhone were used in test, and with all of them pressing on "hold" softphone button led to: participator hear music-on-hold, hold-initiator hear silence. So, both FreeSwitch and Asterisk are so wise that play music-on-hold for person being held and silence for us. "Mute" is similar.

(at least) For Asterisk it is possible to turn of sound in music-on-hold (if you wish to hear silence being held and being free. To do this add line

musiconhold=none

to the specific peer section or to the 'global' if you want to apply this feature for everyone.

Ad notam:

"hold" itself is simply re-INVITE with SDP attributes

IN:0.0.0.0
a:sendonly

Mute. Well, with Asterisk you can mute SIP channel using re-INVITE with "a=receiveonly" in media description. Freeswitch (at least in version 1.0.4 and below) doesn't support this.

Enable SSH for VMware ESX and get access to your virtual machines

2009-05-28T01:53:00.000-07:00

You've deleted virtual appliance with 'remove' or simply pressed 'delete'? Congratulations! Now you have no access to "not_needed" virtual machine (VM) but the disk space is still used..
To remove/restore/whatever_else VM from disk you may:
do it manually (like a God - always without mistakes):

Enable ssh access on VMware ESX 3i
Login to ESX server
Explore /vmfs/volumes/datastore. Your VM is there.

Or use Datastore Browser- utility bundkled with VmWare Infrastructure client:

Select the VmWare ESX server host
Go to tab Summary -> Resources -> Datastore -> double click on your datastore