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Microsoft ISA Server, Part I – introduction, installation, configuration, Web caching and Internet access
http://www.windowsecurity.com/articles/Microsoft_ISA_Server_Part_I__introduction_installation_configuration_Web_caching_and_Internet_access.html
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Hi!
Recently I've been asked if my program can be run on a cluster consisting of 2 Win2K machines and I couldn't give an answer, because I don't know nothing about windows clusters Is anybody here to share some light on the subject of server clustering?
The application in question is a client-server app using .NET remoting for communication. The server part consists of SingleCall CAO's and a class instance published explicitely (using RemotingServices.Marshal() ). The server also operates on a locally installed SQLServer, if this makes any difference.
Can this work out-of-the-box on a cluster? Do I have to modify the program/architecture?
I'd be really grateful for any information on this subject.
Best regards,
mav
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Try to read the below definition:
clusterA group of two or more nodes within a system supporting clustering.<br />
<br />
Overview<br />
When a client on a network tries to access shared resources or applications on a cluster, the cluster appears to the client as a single node or server instead of the group of nodes or servers it really is.<br />
<br />
In the Cluster service of Microsoft Windows 2000 and Windows .NET Server Enterprise Server and Datacenter Server, each node in a cluster is a completely independent computer system that must be running Windows 2000 Enterprise Server. Typically, such nodes are connected by a shared storage bus such as an external Small Computer System Interface (SCSI) disk subsystem or RAID array.<br />
<br />
clustering<br />
Any technology that enables two or more servers to appear to clients as a single system.<br />
<br />
Overview<br />
A cluster consists of a group of computers functioning together as a unit, running a common set of applications, and presenting a single image to client systems. Clustering can be implemented in various ways, but its basic goals are to provide businesses with high availability, high reliability, and high scalability solutions for mission critical business operations.<br />
<br />
Clustering solutions generally come in two basic types:<br />
<br />
<br />
Stateful clustering: The goal of this type of clustering is to provide high availability and high reliability for fast, uninterrupted service in high- demand environments that can tolerate minimal downtime (stateful clustering is not designed to scale applications out to handle more users-this is the purpose of stateless clustering discussed next). Stateful clustering works by connecting independent computer systems into a single entity called a cluster, with each system within the cluster being called a node. Generally some multiple of two is used as the number of nodes within a cluster, for example, 2, 4, 8, 16, or 32 nodes. The different nodes within a cluster are usually connected using a shared disk subsystem which typically consists of a hard disk system or RAID-5 array connected to each node using a fast Small Computer System Interface (SCSI) bus or fiber channel connection. The result is a cluster of computer systems that acts and functions as if it were a single system. In stateful clustering, the nodes within a cluster generally share the workload, and when one node fails its workload fails over (transfers to) another node in the cluster with no interruption of services from the user's perspective. When the failed node comes back online, the workload fails back to this node and normal operation of the cluster resumes. Failover in stateful clustering systems can be implemented in different ways, and this is discussed below. An example of a platform supporting stateful clustering is the Cluster service of Microsoft Windows 2000 Enterprise Server and Datacenter Server. Another name for stateful clustering is shared storage or shared something clustering.<br />
<br />
<br />
Stateless clustering: The goal of this type of clustering is to provide high availability and high reliability by enabling administrators to scale out applications to meet increased demand as the number of users and traffic generated increase. Stateless clustering uses a group of nodes (servers) that are not connected in any way apart from the underlying network connectivity. No failover occurs between nodes when a node in the cluster fails. Instead, some form of load balancing is used to share the workload between the different nodes, and if one node fails the other nodes pick up the extra workload with no interruption of services. Stateless clustering is supported by three Microsoft products: Network Load Balancing (NLB), Component Load Balancing (CLB), and Application Center 2000. Another name for stateless clustering is shared- nothing clustering, and SQL Server 2000 supports a form of shared-nothing clustering known as Federated Server Groups.<br />
<br />
Stateful clustering solutions themselves generally fall into three different categories, depending on if and how failover occurs between different nodes:<br />
<br />
<br />
Active/active clustering: This type of clustering makes the most efficient use of system resources because there are no redundant nodes: all nodes run active processes. If one node of a cluster fails, other nodes take on the failed cluster's workload. The latency for failover in this scenario is typically 15 to 150 seconds, depending on the hardware/software configuration. Active/active clustering is supported by the Cluster service of Microsoft Windows 2000 Enterprise Server and Datacenter Server, and by the Cluster service of Windows .NET Server (discussed later in this article).<br />
<br />
<br />
Active/standby clustering: Nodes are paired within a cluster, with one node designated to take over should another node fail. If an active node fails, a standby node assumes its workload. Latency for failover is also 15 to 150 seconds. Active/standby clustering is a more expensive solution than active/active because the standby node is essentially doing nothing unless the active node fails.<br />
<br />
<br />
Fault-tolerant clustering: Nodes are paired within a cluster, and all nodes perform all tasks simultaneously. This is an expensive solution from a hardware point of view, but latency for failover is reduced to a second or less.<br />
<br />
Marketplace<br />
Many different clustering solutions are in the marketplace, but this article focuses on four different clustering technologies delivered by Microsoft platforms and products, namely:<br />
<br />
Windows clustering, previously known as Microsoft Cluster Services (MCSC)<br />
<br />
Network Load Balancing (NLB)<br />
<br />
Application Center 2000<br />
<br />
Component Load Balancing (CLB)<br />
<br />
You can find additional information in separate articles on each of these four solutions.<br />
<br />
Windows clustering is a feature of Microsoft Windows 2000 Advanced Server and Datacenter Server and of Windows .NET Server. Windows clustering is probably Microsoft's best-known clustering platform and was originally developed for Microsoft Windows NT Server Enterprise Edition where it was code-named Wolfpack during its development. Windows clustering is a stateful clustering solution that enables system architects to create clusters from groups of independent computer systems and to run and manage cluster-aware applications. Using Windows clustering, you can build two-way clusters (that is, clusters with only two nodes) on Windows 2000 and Windows .NET Server Enterprise Server edition or four- way clusters on Windows 2000 and Windows .NET Server Datacenter Server edition (Windows NT Server Enterprise Edition supported only two-way clustering). In Windows clustering a cluster connects nodes together using a shared file system and clusters can utilize active/active clustering for maximum reliability and availability. Windows clustering makes an excellent choice for clustering database and messaging applications for enterprises.<br />
<br />
Network Load Balancing (NLB) is a stateless clustering solution included with Windows 2000 and Windows .NET Server Enterprise Server and Datacenter Server editions, and it was formerly called Windows Load Balancing Services (WLBS) on the Windows NT Server 4 platform. NLB provides load balancing of Internet Protocol (IP) traffic to up to 32 independent network nodes (servers) and is typically used to build farms of Web servers or Exchange 2000 Outlook Web Access (OWA) servers for large enterprises. When one node in an NLB cluster goes down, the load is simply redistributed to the remaining nodes.<br />
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Application Center 2000 is a part of Microsoft Corporation's .NET Server family, and is a stateless clustering platform designed to provide a single point of management for farms of Web servers. Appcenter is typically used in conjunction with NLB and CLB to provide high availibity, high reliability clustering that can scale out to large numbers of users. Appcenter manages a collection of servers in a Web farm as a single entity and can be used to create new clusters, join servers to existing cluster, remove nodes from clusters, deploy applications and application components to different nodes within a cluster, move components between nodes of a cluster, monitor the performance of a cluster, and manage load balancing of network connections to cluster nodes and COM+ components within a cluster-aware application.<br />
<br />
Component Load Balancing (CLB) is supported by all versions of Windows 2000 Server and is used to provide load balancing of COM+ objects across distributed applications deployed on up to 16 nodes (servers). CLB is a stateless clustering solution that requires no special hardware but needs Microsoft Application Center 2000 in order to operate.
Before you write any application relate to the network prcess, you have understand some basic concept of network and the environment that you will deploy your application. Understand network environment for the application that you will install make your distribution computer easy to use your application with less of error opportunity. Ex: type of application that you will distribute, system/application protocol that you will use, default port that to transfer packet... These are the concept of network that developer need to understand before they develop their application.
I got this definition from "Microsoft Encyclopedia of Networking, 2nd Edition" Author: Tulloch, Mitch and Tulloch, Ingrid. Publish by Microsoft Press, ISBN: 0-7356-1378-8.
APO-CEDC
Save Children Norway-Cambodia Office
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Thanks a lot for this overview!
I'll have to digest it for a while
Regards,
mav
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Please inform what log files will be useful to analyse performance issues for sharepoint portal.
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Can anyone direct me to a cmd flag reference?
For instance why is the /c flag used and why is the /k flag used below:
<br />
Sub Copy()<br />
Set objShell = CreateObject("Wscript.Shell") <br />
WScript.Echo("Copying files...")<br />
'WScript.Echo("cmd /c Copy " & strFolderToStartFrom & strFileToCopy & " \tmp\" & strZip) <br />
objShell.Run("cmd /c Copy " & strFolderToStartFrom & strFileToCopy & " \tmp\" & strZip)<br />
'WScript.Echo("cmd /k unzip -l \tmp" & strZip), 1, False<br />
objShell.Run("cmd /k unzip -l \tmp" & strZip), 1, False<br />
Set objShell = Nothing <br />
End Sub<br />
<br />
Thanks for any help anyone can give me with this!
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Hint:
cmd /?
/c means perform the command that follows, and then exit (that is, cmd exits)
/k means perform the command that follows, but don't exit. Normally you wouldn't do this, but the command might leave error messages on screen, and you want a chance to read them...
Steve S
Developer for hire
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Thank you so much for your speedy help!!!
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Hi all,
This morning, i got a problem: "\\remote_compueter_name is not acessible
The network path not found" when accessing to remote computer
I dont know the reason, so pls help me
Thanks in advance
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Restart your computer serveral time, make sure this message still appear or not. If it still appear, it might be you mape a network drive to the remote PC and the remote PC shutdown or have a problem. It it just appear once time and you restart next time appear no problem it mean that your last shutdown did not close a windows that that you open to the remote computer. For more information read this document[^]. And try to search in google.
APO-CEDC
Save Children Norway-Cambodia Office
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Hi,
Why isn't the following code working? A DOS window opens quickly and closes, but the list of zip files is not given...
Thanks for any help you can give me!
<br />
Set objShell = CreateObject("Wscript.Shell") <br />
objShell.Run("unzip -l \tmp\test.zip") <br />
Set objShell = Nothing <br />
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I found a solution, using the command processor. The following, leaves the DOS window open:
<br />
Set objShell = CreateObject("Wscript.Shell")<br />
objShell.Run("cmd /k unzip -l \tmp\test.zip"), 1, False <br />
Set objShell = Nothing <br />
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Hi,
I am trying to convert the following NT Cmd Script to put into a vbs script:
del /Q \tmp\*.zip
When I try the following I get the message "The system cannot find the file specified"
Set objShell = CreateObject("Wscript.Shell")
objShell.Run "del /Q \tmp\*.zip"
Set objShell = Nothing
The filesystemobject does not understand wildcards, so that avenue seems to be closed for me.
Any suggestions or feedback would be greatly appreciated.
Thanks!
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del isn't a program, it's a builtin command in the command interpreter, cmd.exe .
cmd /c "del" ought to do what you want.
Stability. What an interesting concept. -- Chris Maunder
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Thank you so much!!!
Now, how about converting the following to vbs, if you can happen to help me:
<br />
start \\hurricane\shared\bob\hotfixes\ <br />
set /p ZIP1=Enter file's name to be copied:<br />
xcopy /Y %ZIP1% \tmp\INETPUB_DEV.ZIP<br />
unzip -l \tmp\INETPUB_DEV.ZIP<br />
The following does not seem to work:
<br />
Set objShell = CreateObject("Wscript.Shell") <br />
objShell.Run("start \\hurricane\shared\bob\hotfixes\")<br />
ZIP1 = InputBox("Please enter the file to copy")<br />
objShell.Run("xcopy /Y " ZIP1 & " \tmp\INETPUB.ZIP")<br />
objShell.Run("unzip -1 \tmp\INETPUB.ZIP")<br />
Set objShell = Nothing<br />
Is the solution as simple as changing start to cmd /c "start" ,
xcopy to cmd /c "xcopy" , and unzip to cmd /c "unzip"
I'm sorry that I cannot readily see if such a change will work, I am having some system difficulties....
Thanks for whatever help you can give!
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xcopy and unzip are programs; start is a built-in command like del .
Stability. What an interesting concept. -- Chris Maunder
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Thank you so very much for your help!
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Hi, i have a problem with duplicate network drive. My computer (windows xp pro) have C: drive as the system and document drive, I have D: drive as the CDROM drive and E: drive is the map network drive that I mapped from the server. If i log on normally i could access the document on my E: drive on the server. But the problem occure when I plug my USB flash drive before i log on to windows. After I plug it and log on to windows, windows indicate me that could not connect to all network drive. In my computer, i can't find my flas drive but when i go through network drive then it will display the content of my flash drive instead of network drive whether I connecto the the network. If i disconnect USB then my network drive still remain and have the file on my server. But if i plug my flash after i log on to windows, windows will create drive F: for my flash drive without any problem.
My question is: why flash drive replace the network drive? Why don't it create another drive whether i plug my flash drive before i log on to windows?
APO-CEDC
Save Children Norway-Cambodia Office
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When you're not logged in, the mapped drives don't exist, and their assigned drive letters are available for the taking. Plugging in a USB drive is a hardware change, and the system assigns the next available drive letter to it. Logging on causes Windows to enumerate user preferences, including drive mappings, so these are assigned after the USB device is added to the configuration. To get around this, I map drives on other hosts starting with a higher drive letter - R: for instance. I let Windows manage the lower drive letter assignments automatically, knowing that the upper letters are not likely ever to be reassigned by the system.
"My kid was Inmate of the Month at Adobe Mountain Juvenile Corrections Center" - Bumper Sticker in Bullhead City
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Thank you very much for your information.
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I have two VGA adapters in my PC. The problem is when I set the color depth of both devices\monitors to 8bits per pixel then GDI chooses the palette of the primary device as the default palette and uses it to render both the devices. Is it possible to force the GDI to render two devices with their respective palettes.
Muhammad Asif Fayyaz
Design Engineer
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Try to consult with the manual that come with your VGA adapter. I think it might state about this issue to. Make sure that both of your VGA adapter card support multiple adapter card in a single PC. Try to read the information of your mainboard too whether it support both VGA card or not. Contact your nearest computer store of check the website of relate manufacturer to read it online documentation.
APO-CEDC
Save Children Norway-Cambodia Office
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Hi, I have a problem while I need to config router. I just buy LinkPro Broadband ADSL/Camble SOHO Router (Sharing a Broadband Interent Connection). The product feature could view from here[^]. I read the manual before I try to config the router.
First I need to set my IP address to "Automatic obtain...". Then I connect my router to my PC for the first configuration (I use straight connection from PC to router). Then I try to access router by enter the following address in IE (http://192.168.1.1, I follow by the manual). But I have a problem, because I could not see the loging page of the router. It display an error and inform me that "Could not find the server or DNS error". I tried many time to config it but it did not work. Could one have an idea about that?
I need to share the internet connection in my home.
APO-CEDC
Save Children Norway-Cambodia Office
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Off the top of my head: check that your network card is enabled. If your network card and router have Link LEDs on them, check that they're both lit - if not, try a different cable. Make sure you're using a direct, not a cross-over, Ethernet cable. Make sure you're not connecting to an uplink port, if it has any. Make sure you've connected to a LAN port (e.g. the port marked '1') and not to the cable modem port (marked 'WAN') - they appear to use the same connector according to the page you linked to.
If you're sure all that's correct, check that your network card is set to 'Half Duplex' if it offers Half Duplex and Full Duplex settings (this is on the Advanced tab in Device Manager). Full Duplex usually only works if the card and the router are from the same manufacturer - Half Duplex is the standard 10/100Mbps setting. If you're still sure it's all correct, right-click the connection in Network Connections and choose Repair - Windows should try to get a new address from DHCP.
If this still fails, try setting your IP address to 192.168.1.100 with a subnet mask of 255.255.255.0. That should enable you to get to 192.168.1.1 to configure it. Otherwise I can only suggest rebooting the router by unplugging the power and reconnecting. If this still fails, you may need to reset to the factory defaults, by pressing the RESET button on the back. This really is the last resort - I've heard of devices where the 'factory default' firmware actually does not work.
Stability. What an interesting concept. -- Chris Maunder
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Dear Mike, thank you very much for your suggestion. I already done it as you recommend. It is not working, in IE i could not access the router login page but when I ping to it IP address 192.168.1.1 (my computer set to IP: 192.168.1.25) it reply. I try to use FTP by the following command "open 192.168.1.1" for testing purpose only. But it display an error message that "the connection was refused". Tomorrow I will return this router it the computer store and ask them to fix it for me.
APO-CEDC
Save Children Norway-Cambodia Office
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