Steve Schofield Weblog : ASP.NET

Response.write saves the day. Display the last X number of event log records using ASP.NET on a remote machine.

steve schofield — Fri, 03 Apr 2009 02:11:00 GMT

It's been a while since I wrote an ASP.NET app, at least 5 years. :) I needed to query remote servers to get the last X numbers of Event log entries. One snag I ran into was trying to use the DataGrid or GridView controls. I kept getting "Index out of bounds" error when trying to write the Message (Description) part of an event log message. I reverted to my 'old Classic ASP' days and used response.write. I never did find a solution using the built-in controls. For those who want to allow others to view event logs w/o granting local access, your application pool needs the appropriate permissions. I setup the application pool to run as a user that can access event logs. Hope this helps. PS: I even have color coding! :)

Default.aspx

<html>

<table class="style1">
    <tr>
     <tr>
        <td class="style2">
            Number of records:</td>
        <td>
            <asp:DropDownList ID="DropDownList3" runat="server" TabIndex="0">
                <asp:ListItem Selected="True">10</asp:ListItem>
                <asp:ListItem>25</asp:ListItem>
                <asp:ListItem>50</asp:ListItem>
            </asp:DropDownList>
        </td>
    </tr>
        <td class="style2">
            Machine Name:</td>
        <td>
            <asp:DropDownList ID="DropDownList2" runat="server" TabIndex="0">
            <asp:ListItem Selected="True">ServerX</asp:ListItem>
            <asp:ListItem>ServerY</asp:ListItem>
            <asp:ListItem>ServerZ</asp:ListItem>
            </asp:DropDownList>
        </td>
</tr>
    <tr>
        <td class="style2">
            Event Log</td>
        <td>
            <asp:DropDownList ID="DropDownList1" runat="server" TabIndex="1">
                <asp:ListItem Selected="True">Application</asp:ListItem>
                <asp:ListItem>Security</asp:ListItem>
                <asp:ListItem>System</asp:ListItem>
            </asp:DropDownList>
        </td>
    </tr>
</table>
 <br />
<br />
<br />
<br />
<asp:Button ID="Button1" runat="server" Text="Button" />
    <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
        DataKeyNames="TimeGenerated" EnableTheming="False" EnableViewState="False"
        PageIndex="1" PageSize="11">
        <Columns>
            <asp:BoundField DataField="Message" />
            <asp:BoundField DataField="TimeGenerated" HeaderText="Daetime"
                SortExpression="TimeGenerated" />
            <asp:BoundField DataField="Source" HeaderText="Source"
                SortExpression="Source" />
            <asp:BoundField DataField="EntryType" HeaderText="EntryType"
                SortExpression="EntryType" />
        </Columns>
    </asp:GridView>
<asp:DataGrid id="LogGrid" runat="server"
    BorderColor="black"
    BorderWidth="1"
    GridLines="Both"
    CellPadding="3"
    CellSpacing="0"
    Font-Name="Verdana"
    Font-Size="8pt"
    HeaderStyle-BackColor="#aaaadd"
    AutoGenerateColumns="False"
PageSize="25"
Font-Names="Verdana"
>
    <Columns>
      <asp:BoundColumn HeaderText="TOF" DataField="EntryType" />
      <asp:BoundColumn HeaderText="Date/Time" DataField="TimeGenerated"/>
      <asp:BoundColumn HeaderText="Source" DataField="Source"/>
      <asp:BoundColumn HeaderText="Message" DataField="Message"/>
    </Columns>

</body>

</html>

Default.aspx.vb

Partial Class _Default
    Inherits System.Web.UI.Page
       Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If Page.IsPostBack = True Then
          Response.Write(DropDownList2.Text.ToString() & "<br>")

            Dim aLog As New Diagnostics.EventLog
   dim z as integer = DropDownList3.Text
            aLog.MachineName = DropDownList2.Text
            aLog.Log = DropDownList1.Text

'LogGrid.DataSource = aLog.Entries
'LogGrid.DataBind()

            'GridView1.DataSource = aLog.Entries
   'GridView1.DataBind()
            Dim y As Integer = 0
            Response.Write("<table border=2 cellpadding=2 width='100%'>")
            Response.Write("<b><tr><td>Counter</td><td>TOF</td><td>TimeGenerated</td><td>Source</td><td>Message</td></tr></b>")
            Dim item As Diagnostics.EventLogEntry
            For Each item In aLog.Entries
                y = y + 1
                If y = z Then
                    Exit For
                End If
                Response.Write("<tr>")
                Response.Write("<td>" & y & "</td>")
                Response.Write("<td>" & aLog.Entries.Item(aLog.Entries.Count - y).EntryType.ToString() & "</td>")
                Response.Write("<td bgcolor='#FFFF99'>" & aLog.Entries.Item(aLog.Entries.Count - y).TimeGenerated.ToString() & "</td>")
                Response.Write("<td>" & aLog.Entries.Item(aLog.Entries.Count - y).Source.ToString() & "</td>")
                Response.Write("<td bgcolor='#FFFF99'>" & aLog.Entries.Item(aLog.Entries.Count - y).Message.ToString() & "</td>")
                Response.Write("</tr>")
            Next
            Response.Write("</table>")
        End If
    End Sub
End Class

Here is the event log class reference on MSDN

http://msdn.microsoft.com/en-us/library/system.diagnostics.eventlog.aspx

Cheers,

Steve

IIS and .NET 2.0 interview questions

steve schofield — Thu, 09 Aug 2007 12:17:00 GMT

I had a 2 hour layover and was browsing the newsgroups. A person posted a question wondering about interview questions regarding IIS and .NET 2.0. I'm sure there are many other questions that I didn't think to ask, here is the list I came up with. If you have any questions, feel free to post them to the comments and I'll update the thread.

PS: This is meant for a 'systems' or 'itpro' type person and not necessarily a developer type individual.

General IIS related questions

How do you isolate and troubleshoot an ASP and / or ASP.NET application?
What is your idea of locking down a server?
How do you feel about having developers or anyone else making changes directly in production? Aka how do you normally handle change management.
What perfmon counters do you find useful in troubleshooting an IIS or related problem.
Do you have experience in working with web-farms, load-balancing environments?
What is your ideal way of handling content. Remote Storage / NAS (network attached storage) vs. local content and replication. If you use local content and replication what tools do you to use?
Are you familiar with DFS?
What debugging tools do you use for IIS?
What / Where would you put global .NET settings. How would you lock them down?
Do you have any experience with SSL certificates?
Do you have experience with machines with multiple IP's and how to handle several sites / applications on a machine.
What is your preference of handling machine accounts? Do you like local vs. Active Directory based accounts.
Do you have experience with working in an AD environment that supports IIS.
Do you have experience with NLB (network load balancing) that comes with IIS.
How do you monitor the applications / sites to ensure the uptime is appropriate. This might apply more to a monitoring environment, but it is good to know what to monitor.
Are you familiar with compression and the benefits.
Do you know what MIME types are for?
Do you know how to list all running applications on a server to determine which application pools are owned by what sites. (IISAPP)
Are you familiar with IISState, IIS Debug Diag. SSL Diag, SMTPDiag in the resource kit.
What tools do you use or have experience in load-testing an application.
What are some of the tools provided by MS. WCAT, TinyGet, WAST.
Do you know how to configure host-headers and how they related to DNS.
What is your backup and recovery strategy for IIS
How would you handle migrating to another box?
How do you handle changes in IIS, scripting or manual changes?
Are you familiar with scripting languages such as VBScript, JScript, Powershell.
Are you familiar with IISCfg and related scripts such as adsutil
Do you have experience supporting multiple environments of IIS (different domains, dev / test /integration / production)
Are you familiar with ways to connect to remote databases such as db2, oracle, sql server
Do you know the differences between anonymous, integrated, basic, digest authentication.
What is your preferred method of publishing content? FTP? FrontPage? WebDAV? Folder copy? Publish to a staging machine and replicate to the content source either on a nas or individual nodes.
Are you familiar with the other services in SMTP, FTP?
Do you know how to configure a smarthost?
Does the built-in FTP service support host-headers?
Do you know the benefits of using a COM+ package vs. Regsvr32
What certain local group is necessary if it is configured as a application pool user.
Do you know how to check a COM+ component to ensure it will not leak memory.

.NET 2.0

Can you run the 1.1 and 2.0 on the same box? What are the limitations.
Can you explain what the '/bin' folder is used for.
Do you know what user instancing is.
Do you know the difference between precompiled applications and publishing the source code.
Do you have any experience with partial trust or CAS (code access security)
What types of things cause an appdomain or application pool recycle.
What are the new folders in .NET 2.0 and what are they used for.
How / why does the machine key need to be the same across all machines in a web-farm.

IIS7

What makes the IUSR account unique in IIS7 vs. previous versions.
What are some of the new ways of troubleshooting, Logging in IIS7
What are the major benefits of IIS7? (FREB, Integrated Pipeline, IUSR same on all w2k8 boxes, Shared configuration, Modular architecture, configuration changes

Changing ASP.net script mapping default

steve schofield — Sat, 07 Jul 2007 04:09:00 GMT

I've ran across this a few times, so I thought I'd put a blog posting on it for future reference.

http://forums.iis.net/t/1108591.aspx

IIS7 - post #31 - Adrotator on IIS7 / Vista / BC32400: Class 'CLSID_CorSymWriter' could not be created: Access is denied.

steve schofield — Fri, 23 Feb 2007 18:47:00 GMT

I was working with the Adrotator component included in .NET 2.0 on Vista and IIS7. I was getting this error; BC32400: Class 'CLSID_CorSymWriter' could not be created: Access is denied. It worked on my other vista machine, so I knew it was specific to my machine. I ran Process Monitor (aka Filemon) and found two registry keys that were getting denied. After adding Network Service with READ permissions, this started working. PS: It was fun to actually use Filemon to track down a problem of my own, I mention this tool in many newsgroup posting.

Here is a picture of the output.

Here is the raw output of the error

Server Error in '/' Application.
--------------------------------------------------------------------------------

Compilation Error
Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.

Compiler Error Message: BC32400: Class 'CLSID_CorSymWriter' could not be created: Access is denied.

Source Error:

[No relevant source lines]

Source File: vbc : Line: 0

Show Detailed Compiler Output:

c:\windows\system32\inetsrv> "C:\Windows\Microsoft.NET\Framework\v2.0.50727\vbc.exe" /t:library /utf8output /R:"C:\Windows\assembly\GAC_32\System.Web\2.0.0.0__b03f5f7f11d50a3a\System.Web.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.ServiceModel\3.0.0.0__b77a5c561934e089\System.ServiceModel.dll" /R:"C:\Windows\assembly\GAC_32\System.Data\2.0.0.0__b77a5c561934e089\System.Data.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.Web.Mobile\2.0.0.0__b03f5f7f11d50a3a\System.Web.Mobile.dll" /R:"C:\Windows\assembly\GAC_32\System.EnterpriseServices\2.0.0.0__b03f5f7f11d50a3a\System.EnterpriseServices.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.Xml\2.0.0.0__b77a5c561934e089\System.Xml.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.Runtime.Serialization\3.0.0.0__b77a5c561934e089\System.Runtime.Serialization.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.Configuration\2.0.0.0__b03f5f7f11d50a3a\System.Configuration.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.IdentityModel\3.0.0.0__b77a5c561934e089\System.IdentityModel.dll" /R:"C:\Windows\assembly\GAC_MSIL\System\2.0.0.0__b77a5c561934e089\System.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.Web.Services\2.0.0.0__b03f5f7f11d50a3a\System.Web.Services.dll" /R:"C:\Windows\assembly\GAC_MSIL\System.Drawing\2.0.0.0__b03f5f7f11d50a3a\System.Drawing.dll" /out:"C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\root\26676eb7\92c7e946\App_Web_ads.aspx.cdcab7d2.p_oyg97i.dll" /D:DEBUG=1 /debug+ /define:_MYTYPE=\"Web\" /imports:Microsoft.VisualBasic,System,System.Collections,System.Collections.Specialized,System.Configuration,System.Text,System.Text.RegularExpressions,System.Web,System.Web.Caching,System.Web.SessionState,System.Web.Security,System.Web.Profile,System.Web.UI,System.Web.UI.WebControls,System.Web.UI.WebControls.WebParts,System.Web.UI.HtmlControls "C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\root\26676eb7\92c7e946\App_Web_ads.aspx.cdcab7d2.p_oyg97i.0.vb" "C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\root\26676eb7\92c7e946\App_Web_ads.aspx.cdcab7d2.p_oyg97i.1.vb"

vbc : error BC32400: Class 'CLSID_CorSymWriter' could not be created: Access is denied.
vbc : error BC31019: Unable to write to output file 'C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\root\26676eb7\92c7e946\App_Web_ads.aspx.cdcab7d2.p_oyg97i.pdb': Access is denied.

--------------------------------------------------------------------------------
Version Information: Microsoft .NET Framework Version:2.0.50727.312; ASP.NET Version:2.0.50727.312

Steve Schofield
Microsoft MVP - IIS

Cool post about.....us!

steve schofield — Fri, 14 Jul 2006 13:41:00 GMT

Steve Smith (ASPAlliance.com) recently blogged about his hosting experience with us (ORCSWeb.com). Here is the link to the post. http://aspadvice.com/blogs/ssmith/archive/2006/07/14/19652.aspx It is a bit of a shame-less post too, I am mentioned for being an 'ubergeek', which I am. [:)] Thanks Steve for the nice comments! If you need a great ASP/ASP.Net resource, http://aspalliance.com is a great site to bookmark.

Joe Stagner presenting at our July 20th (GLUGnet) user group meeting.

steve schofield — Mon, 26 Jun 2006 00:37:00 GMT

Mark your calender, here is information about our next user group meeting! The evolution of the Web Application User Experience with Microsoft Atlas - Web 2.0 & AJAX are the buzzwords of the next generation of web development. This session will provide a look into Microsoft’s new Web Development technology “Atlas”. Atlas combines rich, cross browser client side libraries with ASP.NET’s popular server side development technology to offer an ideal developer’s toolbox for developing the next generation of Web Applications.

Speaker: - Joe Stagner (http://www.joeon.net/) is a Program Manager in Microsoft Corporation’s Developer Tools and Platform Group and has been with Microsoft since 2001 focusing on highly scalable and performant web application architectures, multiplatform interoperability and software security. Joe brings 30 years technical and business strategy experience to Microsoft which affords him a unique experiential perspective.

Sponsor: GLUGnet.

!!-Prizes: Dell 19inch LCD monitor, books, and other cool swag will be given out for our July meeting-!!

Looking for SMTP service in IIS 7 / Longhorn beta 2.

steve schofield — Mon, 29 May 2006 04:00:00 GMT

I was looking to install SMTP service and could not find under the "web server" role. Here are the instructions in the help file. Hope this helps.

How to Add Features to Your Server
In Windows Server "Longhorn" Beta 2, you can add most available features to your server by using the Add Features Wizard.

Adding Features to Your Server by Using the Add Features Wizard

Adding Features to Your Server by Using the Add Features Wizard
You can add the following features by using the Add Features Wizard.

Windows Activation Service (WAS)
Background Intelligent Transfer Service (BITS) Server Extensions
Desktop Experience
Windows Clustering
Windows Server Backup
Line Print Remote Port Monitor
Microsoft Message Queuing (MSMQ) Services
Windows Network Load Balancing
Remote Access Service (RAS) Client
Remote Assistance
Remote Procedure Calls over HTTP Proxy
Simple Mail Transfer Protocol (SMTP) Server
Storage Manager for Storage Area Networks
Simple TCP/IP Services
Subsystem for UNIX-based Applications
Telnet Client
Telnet Server
Windows Internal Database
Windows Internet Name Service (WINS)
Windows System Resource Manager (WSRM)
Windows Foundation Components for WinFX
Wireless Networking
SQL Server 2005 Embedded Edition (Windows)
iSNS Server
Windows Search Service
Indexing Service
Bitlocker Drive Encryption

Open the Add Features Wizard in one of the following two ways.

To start the Add Features Wizard
In the Features Summary area of the Server Manager main window, click Add Features.

-- or --

In the Customize this server area of the Initial Configuration Tasks window, click Add Features.

Note
The Initial Configuration Tasks window opens by default when a member of the Administrators group logs on to the computer.

Server Manager opens when the Initial Configuration Tasks window is closed. You can also open Server Manager by using shortcuts on the Start menu or in Administrative Tools.

Steve Schofield
Microsoft MVP - ASP/ASP.NET
ASPInsider Member - MCP

http://www.orcsweb.com/
Managed Complex Hosting
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