Sao lưu: Incremental hay Differential?

Một số các bạn có thói quan sao lưu dữ liệu (backup) – vậy thì quá tốt – bởi vì tôi đã gặp rất nhiều người hỏi cùng 1 câu hỏi: làm sao cứu dữ liệu của tôi – 80% đã quá trễ, 20% tốn từ 2tr đến 4tr để cứu những gì có thể cứu được. Do vậy, “backup or die”.
Các bạn nếu có dùng phần mềm backup sẽ hay nghe nói phần mềm này rất chuyên nghiệp, có tính năng backup “Incremental” và “Differential”. Vậy thì 2 thuật ngữ này là gì?
Về cơ bản, có 3 phương pháp backup: Full, Differential, và Incremental.
1. Full backup
Tên như người – nghĩa là backup tất cả
Ví dụ minh họa:

• Bạn có 1 file text A.txt nội dung là 1 2 3 4
• Bạn cấu hình Full backup hằng ngày vào buổi tối – phần mềm backup sẽ sao lưu y chang File đó mỗi ngày

Lợi điểm:

• Dễ phục hồi dữ liệu (restore).

Ví dụ minh họa như trên:
Giả sử bạn cần phục hồi dữ liệu về thời điểm Thứ Bảy: Bạn chỉ cần 1 bản Full backup của tối Thứ Bảy
Bất lợi:

• Tốn thời gian và dung lượng backup.

Tưởng tượng bạn có 10TB dữ liệu – mỗi bản Full backup lại 10TB nữa, 1 tuần backup mất 70TB – quá nhiều.
Trong thực tế, không áp dụng Full backup hằng ngày cho khối lượng dữ liệu lớn.
2. Differential backup
Backup những gì thay đổi so với lần Full backup gần nhất

Ví dụ minh họa:

• File text A.txt có nội dung 1 2 3 4
• Cấu hình backup: Full backup vào Chủ Nhật, Differential backup vào Thứ Hai, Thứ Ba, Thứ Tư, Thứ Năm, Thứ Sáu, và Thứ Bảy.

Giả sử Thứ Hai bạn sửa nội dung A.txt thành 1 2 3 4 5 –> Differential backup sẽ chỉ sao lưu phần thay đổi: 5
Giả sử Thứ Ba bạn sửa nội dung A.txt thành 1 2 3 4 5 6 –> Differential backup sẽ chỉ sao lưu phần thay đổi: 5 6
Lợi điểm:

• Tiết kiệm thời gian và dung lượng backup.
• Restore nhanh hơn so với Full backup

Bất lợi:

• Restore cần đủ file: 1 File Full backup lần gần nhất và 1 File Differential backup vào thời điểm cần restore

Ví dụ minh họa nêu trên:
Giả sử bạn cần restore file về thời điểm Thứ Ba – bạn cần có file Full Backup của Chủ Nhật và Differential backup của Thứ Ba
3. Incremental backup
Backup những gì thay đổi so với lần Incremental backup gần nhất

Ví dụ minh họa:

• File text A.txt có nội dung 1 2 3 4
• Cấu hình backup: Full backup vào Chủ Nhật, Incremental backup vào Thứ Hai, Thứ Ba, Thứ Tư, Thứ Năm, Thứ Sáu, và Thứ Bảy.

Giả sử Thứ Hai bạn sửa nội dung A.txt thành 1 2 3 4 5–> Incremental backup sẽ chỉ sao lưu phần thay đổi: 5
Giả sử Thứ Ba bạn sửa nội dung A.txt thành 1 2 3 4 5 6 –> Incremental backup sẽ chỉ sao lưu phần thay đổi: 6
Lợi điểm:

• Tốn ít thời gian và dung lượng sao lưu nhất.

Bất lợi:

• Restore cần đủ file: 1 File Full backup lần gần nhất và tất cả các File Incremental backup từ thời điểm Full backup đến thời điểm cần restore
• Restore lâu hơn so với Differential Backup.

Ví dụ minh họa nêu trên:
Giả sử bạn cần restore file về thời điểm Thứ Ba – bạn cần có file Full Backup của Chủ Nhật và Incremental backup của Thứ Hai và Incremental backup của Thứ Ba
Trong thực tế, cấu hình backup phổ biến nhất là:

• Full Backup hàng tháng.
• Differential Backup hàng tuần.
• Incremental Backup hàng ngày.

Chúc các bạn luôn an toàn trên xa lộ thông tin :).

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Posted in: Backup

SBS 2008 Using the POP Connector

To access the Windows Small Business Server POP3 Connector properties

1. Open the Windows SBS Console.
   
2. On the navigation bar, click Network.
   
3. Click the Connectivity tab.
   The list view displays information about your network connections.
   
4. In the list view, click POP3 Connector.
   
5. In the Tasks pane, click View POP3 Connector properties.
   

To view error messages for the POP3 Connector

1. Click Start, type eventvwr, and then press ENTER.
   
2. In the console tree, expand Applications and Service Logs.
   
3. Expand Windows Small Business Server 2008, and then select Microsoft Windows Small Business Server/Operational.
   The details pane displays error and event messages for Windows SBS 2008 including error messages from the POP3 Connector.
   

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Posted in: Exchange

Link to original Microsoft article:
http://support.microsoft.com/kb/912375/

How to increase the Exchange Server 2003 Service Pack 2 database size limit

To increase the Exchange Server 2003 SP2 database size, follow these steps.

Important Before you increase the maximum size of an Exchange database, verify that sufficient hard disk space is available for the larger database.

1. On the computer that is running Exchange 2003 SP2, click Start, click Run, type regedit, and then click OK.
2. Click one of the following registry subkeys, as appropriate for the store that you want to increase:
   • For a mailbox store, click the following registry subkey:
     HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\Server name\Private-Mailbox Store GUID
   • For a public folder store, click the following registry subkey:
     HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\Server name\Public-Public Store GUID
3. On the Edit menu, point to New, and then click DWORD Value.
4. In the New Value #1 box, type Database Size Limit in Gb, and then press ENTER.
5. Right-click Database Size Limit in Gb, and then click Modify.
6. Click Decimal, and then type an integer from 1 to 75 in the Value data box.
   
   Note These integer values represent the maximum size of the database in gigabytes (GB). For example, a value of 75 represents a database that has a maximum size of 75 GB.
7. Click OK, and then exit Registry Editor.
8. Restart the Microsoft Exchange Information Store service. To do this, follow these steps:
   1. Click Start, click Run, type cmd, and then click OK.
   2. At the command prompt, type the following command, and then press ENTER:
      net stop msexchangeis
   3. After the Microsoft Exchange Information Store service has stopped successfully, type the following command, and then press ENTER:
      net start msexchangeis
9. Examine the Application log to verify that the database size has been set successfully. To do this, follow these steps:
   1. Click Start, click Run, type eventvwr, and then click OK.
   2. In the Event Viewer tool, click Application.
   3. Double-click event ID 1216 to verify that the database size has been set successfully.

To determine if you're running Exchange Server 2003 SP2:

1. Open Exchange System Manager
2. Expand 'Servers'
3. Right-click on [server name], choose Properties
4. On the General tab, verify that the version is Version 6.5 (Build 7638.2: Service Pack 2)

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Fix Outlook 2007 Certificate Errors

For SBS 2008 run the following commands in Exchange Management Shell:

Set-ClientAccessServer -Identity yourserver -AutodiscoverServiceInternalUri https://external.yourdomain.com/autodiscover/autodiscover.xml
Set-WebServicesVirtualDirectory -Identity “yourserver\EWS (SBS Web Applications)” -InternalUrl https://external.yourdomain.com/ews/exchange.asmx
Set-OABVirtualDirectory -Identity “yourserver\oab (SBS Web Applications)” -InternalUrl https://external.yourdomain.com/oab
Set-UMVirtualDirectory -Identity “yourserver\unifiedmessaging (SBS Web Applications)” -InternalUrl https://external.yourdomain.com/unifiedmessaging/service.asmx

For Exchange 2007 Standard or Enterprise on Windows Server 2008 run the following commands in Exchange Management Shell:
Set-ClientAccessServer -Identity yourserver -AutodiscoverServiceInternalUri https://external.yourdomain.com/autodiscover/autodiscover.xml
Set-WebServicesVirtualDirectory -Identity “yourserver\EWS (Default Web Site)” -InternalUrl https://external.yourdomain.com/ews/exchange.asmx
Set-OABVirtualDirectory -Identity “yourserver\oab (Default Web Site)” -InternalUrl https://external.yourdomain.com/oab
Set-UMVirtualDirectory -Identity “yourserver\unifiedmessaging (Default Web Site)” -InternalUrl https://external.yourdomain.com/unifiedmessaging/service.asmx
If you’re not sure which set of commands to use, type Get-WebServicesVirtualDirectory in Exchange Management Shell and see what is listed for name. You will either see EWS (SBS Web Applications) or EWS (Default Web Site). Match that up with the command set above and it should find the appropriate virtual directories.
On Windows Server 2008, if you see access denied errors then make sure you use Run As Administrator to run Exchange Management Shell.

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Posted in: Exchange,Outlook

Exchange 2007 Autodiscover Issues

We have recently begun installing a lot of Exchange 2007 servers, both Exchange 2007 standard and as part of SBS 2008. Starting with Exchange 2003 there is a lot of reliance on the web services part of the server which reside in IIS. In order to get things working properly we get a SSL certificate, usually from GoDaddy, to secure the exchange directories. This allows us to set up devices with Exchange Activesync, OWA without certificate warnings, and Outlook Anywhere.
We’ve noticed that when installing these certificates, Outlook clients on the domain begin to see a certificate error. This is because of the Autodiscover URLs that are part of Exchange server and the fact they no longer match the self-signed certificate that Exchange produces on installation.
In order to update those URLs you need to use Exchange Management Shell to run some commands. The commands are different for SBS installations and Standard installations. In the following commands, replace yourserver with the netbios name of your Exchange server and external.yourdomain.com with the external address of your server.
For SBS 2008 run the following commands in Exchange Management Shell:
Set-ClientAccessServer -Identity yourserver -AutodiscoverServiceInternalUri https://external.yourdomain.com/autodiscover/autodiscover.xml
Set-WebServicesVirtualDirectory -Identity “yourserver\EWS (SBS Web Applications)” -InternalUrl https://external.yourdomain.com/ews/exchange.asmx
Set-OABVirtualDirectory -Identity “yourserver\oab (SBS Web Applications)” -InternalUrl https://external.yourdomain.com/oab
Set-UMVirtualDirectory -Identity “yourserver\unifiedmessaging (SBS Web Applications)” -InternalUrl https://external.yourdomain.com/unifiedmessaging/service.asmx
For Exchange 2007 Standard or Enterprise on Windows Server 2008 run the following commands in Exchange Management Shell:
Set-ClientAccessServer -Identity yourserver -AutodiscoverServiceInternalUri https://external.yourdomain.com/autodiscover/autodiscover.xml
Set-WebServicesVirtualDirectory -Identity “yourserver\EWS (Default Web Site)” -InternalUrl https://external.yourdomain.com/ews/exchange.asmx
Set-OABVirtualDirectory -Identity “yourserver\oab (Default Web Site)” -InternalUrl https://external.yourdomain.com/oab
Set-UMVirtualDirectory -Identity “yourserver\unifiedmessaging (Default Web Site)” -InternalUrl https://external.yourdomain.com/unifiedmessaging/service.asmx
If you’re not sure which set of commands to use, type Get-WebServicesVirtualDirectory in Exchange Management Shell and see what is listed for name. You will either see EWS (SBS Web Applications) or EWS (Default Web Site). Match that up with the command set above and it should find the appropriate virtual directories.
On Windows Server 2008, if you see access denied errors then make sure you use Run As Administrator to run Exchange Management Shell.
At this point, we have solved problems with Autodiscover that resulted in error messages in Outlook clients but have not actually set up Autodiscover. The Autodiscover setup process usually includes setting up a new site in IIS for autodiscover.yourdomain.com and adding the autodiscover virtual directory to it. You’ll also need a SSL cert for it which is why we don’t usually set it up. We have yet to see any advantages to setting up Autodiscover since our clients usually don’t have that many clients connected to their Exchange server.

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Posted in: Exchange

Exchange - Build Numbers and Release Dates

Version                          Build number              Release date

Server  4.0                      4.0.837                   April 1996

Server  4.0 (a)                  4.0.993                   August 1996

Server  4.0 SP1                  4.0.838                   May 1996

Server  4.0 SP2                  4.0.993                   August 1996

Server  4.0 SP3                  4.0.994                   November 1996

Server  4.0 SP4                  4.0.995                   April 1997

Server  4.0 SP5                  4.0.996                   May 1998

Server  5.0                      5.0.1457                  March 1997

Server  5.0 SP1                  5.0.1458                  June 1997

Server  5.0 SP2                  5.0.1460                  February 1998

Server  5.5                      5.5.1960                  November 1997

Server  5.5 SP1                  5.5.2232                  July 1998

Server  5.5 SP2                  5.5.2448                  December 1998

Server  5.5 SP3                  5.5.2650                  September 1999

Server  5.5 SP4                  5.5.2653                  November 2000

2000 Server                      6.0.4417                  October 2000

2000 Server (a)                  6.0.4417                  January 2001

2000 Server SP1                  6.0.4712                  July 2001

2000 Server SP2                  6.0.5762                  December 2001

2000 Server SP3                  6.0.6249                  August 2002

2000 Server post-SP3             6.0.6487                  September 2003

2000 Server post-SP3             6.0.6556                  April 2004

2000 Server post-SP3             6.0.6603                  August 2004

Server  2003                     6.5.6944                  October 2003

Server  2003 SP1                 6.5.7226                  May 2004

Server  2003 SP2                 6.5.7638                  October 2005

Server  2007                     8.0.685.24 or 8.0.685.25  December 2006

Server  2007 SP1                 8.1.0240.006              November 2007

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Changing SBS 2008 Exchange Mailbox Limits

In Windows SBS 2008, the mailbox database and the individual mailboxes have a size limit of 2 GB. If the size limit of the mailbox database or the individual mailboxes on the Source Server is more than 2 GB, you must manually change the size limits on the Destination Server

To change the size limit of the mailbox database

1. On the Destination Server, click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Console.
   
2. Click Continue in the User Account Control dialog box.
   
3. In the Exchange Management Console navigation pane, expand the Server Configuration node, and then click Mailbox.
   
4. In the result pane, click the Destination Server name.
   
5. In the work pane, right-click Mailbox Database, and then click Properties.
   
6. Click the Limits tab, specify the mailbox database limits, and then click OK.
   

To change the size limit of the individual mailboxes

1. On the Destination Server, open the Windows SBS Console.
   
2. In the navigation bar, click the Users and Groups tab, and then click Users.
   
3. Click a user account, and then click Edit user account properties.
   
4. Click the E-Mail tab, update the maximum mailbox size information, and then click OK.
   
5. Repeat steps 3 and 4 until all user accounts are updated.
   

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Posted in: Exchange

Changing Exchange 2003 Message Size Limits

To change the default limits for sending and receiving message size

1. In Exchange System Manager, expand Global Settings. Right-click Message Delivery and then click Properties.
   
2. Select the Defaults tab.
   
3. Change the limits for Sending Message Size and Receiving Message Size.
   

To change the size limit of the individual mailboxes

1. On the Exchange Server, open Active Directory Users and Computers.
   
2. Select the user for which you would like to change message size limits, then right-click and click Properties.
   
3. Select the Exchange General tab.
   
4. Click on Delivery Restrictions.
   
5. Set the Sending Message Size and Receiving Message Size and click OK.
   

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Posted in: Exchange

Malware Removal Tools

The following is a listing of most common virus/malware/rootkit removal tools:

General Removal Tools

Malwarebytes' Anti-Malware: http://www.majorgeeks.com/MBAM_d5756.html

A very good free malware scanner. It will find and remove most types of malware automatically.

Trend Micro HijackThis: http://free.antivirus.com/hijackthis/

HijackThis is a malware scanner and removal tool that can find and remove Browser Helper Objects, auto run processes, and malware services.

ComboFix: http://download.bleepingcomputer.com/sUBs/ComboFix.exe

ComboFix is a malware scanner and removal tool that can remove most types of malware.

Rootkit Removal Tools

Sophos Anti-Rootkit: http://www.sophos.com/products/free-tools/sophos-anti-rootkit.html

Sophos Anti-Rootkit is a malware scanner and removal tool. It scans for hidden files, registry keys, and running processes that can indicate a rootkit.

Malware Scanners

GMER: http://gmer.net/download.php

GMER is a thorough malware scanner only. It assists in finding hidden rootkits.

RootRepeal: http://download.bleepingcomputer.com/rootrepeal/RootRepeal.exe

RootRepeal is another malware scanner and reporting tool.

Sysinternals RootkitRevealer: http://technet.microsoft.com/en-us/sysinternals/bb897445.aspx

Rootkit Revealer is a malware scanner that compares API results from user mode and kernel mode calls that may indicate a rootkit is hiding itself.

Specific Malware Removal Tools

Kaspersky TDSSKiller: http://support.kaspersky.com/viruses/solutions?qid=208280684

Assists in removal of TDSS related rootkits.

Trend Micro CWShredder: http://free.antivirus.com/cwshredder/

CWShredder is a malware scanner and removal tool specifically targeted at removing CoolWebSearch

GooRedFix: http://forums.majorgeeks.com/showthread.php?t=182559

GooRedFix is a maleware scanner that looks for browser redirection malware.

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Posted in: Malware

Malware Removal Registry Scripts

Script to repair running of .exe files

Windows Registry Editor Version 5.00

[-HKEY_CURRENT_USER\Software\Classes\.exe]
[-HKEY_CURRENT_USER\Software\Classes\secfile]
[-HKEY_CLASSES_ROOT\secfile]
[-HKEY_CLASSES_ROOT\.exe\shell\open\command]

[HKEY_CLASSES_ROOT\exefile\shell\open\command]
@="\"%1\" %*"

[HKEY_CLASSES_ROOT\.exe]
@="exefile"
"Content Type"="application/x-msdownload"

Script to re-enable task manager

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"DisableTaskMgr"=dword:00000000

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Group Policy Objects\LocalUser\Software\Microsoft\Windows\CurrentVersion\Policies\System]
"DisableTaskMgr"=dword:00000000

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system\]
"DisableTaskMgr"=dword:00000000

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"DisableCAD"=dword:00000000

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Posted in: Malware

How to install NTBackup on Server 2008

In order to install the Windows XP Ntbackup program on Server 2008 or Windows Vista computer you will need to following files from a Windows XP computer:

Ntbackup.exe
Ntmsapi.dll
Vssapi.dll
These can be found in the C:\Windows\System32 folder of Windows XP or downloaded directly from ftp://ftp.bitsmail.com/Knowledgebase/NTBackup.zip
You could also copy these help files, but you don't really need them: Ntbackup.chm, Ntbackup.hlp
These can be found in the C:\Windows\Help folder of Windows XP.
Copy all 3 (or 5) files to a folder in your Vista or Server 2008 'Program Files' folder, for example use C:\Program Files\Ntbackup. Since you won't be pasting these files in the system path there is no need to worry about overwriting files.
Next, you will need to turn on or install the Removable Storage Management feature (you will get an NTSMAPI.dll error if Removable Storage Management is not enabled).

Vista

1. Click the Start button > Control Panel > Programs, and then click Turn Windows Features on or off. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
2. Select the check box next to Removable Storage Management to turn the feature on, and then click OK. 
3. Now, create a shortcut for Ntbackup.exe on your Desktop, calling it something like "Original Ntbackup" or whatever.
4. Click on that shortcut (or directly on the Ntbackup.exe file if you so desire), and bingo, you can begin to manually backup and restore ANY file you want, and you are NO LONGER LIMITED by Vista's Backup Status and Configuration tool.

Server 2008

1. Click the Start button and in the 'Start Search' box type (or paste):  servermanagercmd -install Removable-Storage
2. Now, create a shortcut for Ntbackup.exe on your Desktop, calling it something like "Original Ntbackup" or whatever.
3. Click on that shortcut (or directly on the Ntbackup.exe file if you so desire), and bingo, you can begin to manually backup and restore ANY file you want, and you are NO LONGER LIMITED by Server 2008's Windows Backup.

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Posted in: Knowledge Base,Windows Server 2008