<br><font size=2 face="sans-serif">Hi Stacey</font>
<br>
<br><font size=2 face="sans-serif">We are experiencing the same issues with a similar multi-tiered system using datasnap/midas and were actually just discussing this issue when these postings came through. </font>
<br><font size=2 face="sans-serif">Until now we have been using e-mail messages as a means of trying to locate problems, but obviously have to limit the number of messages sent so it is not always catching the issues. We were just kicking around the same basic idea that Dave Jollie replied with and think that this would be the best solution, we curently have the Server app with the ability to run in debug mode "where messages are sent" or standard mode " no messages". </font>
<br><font size=2 face="sans-serif">It is now just a matter of finding the actual time to retro fit to existing code..</font>
<br><font size=2 face="sans-serif">But will certainly let you know if we find anything obvious...</font>
<br>
<br><font size=2 face="sans-serif">Cheers</font>
<br><font size=2 face="sans-serif">Robert Wilson<br>
</font>
<br>
<br>
<br>
<table width=100%>
<tr valign=top>
<td>
<td><font size=1 face="sans-serif"><b>"Stacey Verner" <stacey@cjntech.co.nz></b></font>
<br><font size=1 face="sans-serif">Sent by: delphi-bounces@ns3.123.co.nz</font>
<p><font size=1 face="sans-serif">02/09/2005 09:48 a.m.</font>
<br><font size=1 face="sans-serif">Please respond to NZ Borland Developers Group - Delphi List</font>
<br>
<td><font size=1 face="Arial"> </font>
<br><font size=1 face="sans-serif"> To: "NZ Borland Developers Group - Delphi List" <delphi@ns3.123.co.nz></font>
<br><font size=1 face="sans-serif"> cc: </font>
<br><font size=1 face="sans-serif"> Subject: [DUG] DataSnap/Midas App Server Error</font></table>
<br>
<br>
<br><font size=2 face="Arial">We have an DataSnap/Midas app server which fails randomly.</font>
<br><font size=3 face="Times New Roman"> </font>
<br><font size=2 face="Arial">We can't make it happen no matter how hard we try, but it happens fairly regularly on our production machine.</font>
<br><font size=3 face="Times New Roman"> </font>
<br><font size=2 face="Arial">A little bit of info on the app and app server:</font>
<ul>
<li><font size=2 face="Arial">The applicaiton is a normal database application.</font>
<li><font size=2 face="Arial">The application also needs to get information from a settings (metadata) database such as:</font>
<ul>
<li><font size=2 face="Arial">Which databases they have access to</font>
<li><font size=2 face="Arial">What permissions they have on the database etc</font></ul>
<ul>
<li><font size=2 face="Arial">Instead of connecting directly to the settings database we use the app server which shares one database connection between all clients.</font>
<ul>
<li><font size=2 face="Arial">This means that there is one database connection for each application instead of 2 which reduces licencing costs</font></ul>
<ul>
<li><font size=2 face="Arial">We use the borland socket server and a socket connection to connect to the app server.</font>
<ul>
<li><font size=2 face="Arial">When we used a normal DCOM connection each client got its own copy of the app server, so the settings database connection is not shared and in effect each application had two connections to the database.</font>
<br><font size=2 face="Arial">Sometimes the app server locks up and the clients can't connect.</font>
<br><font size=3 face="Times New Roman"> </font>
<br><font size=2 face="Arial">We have a work around that will try app servers on other machines if this fails which works OK, but if it never gets a connection the all sorts of odd things happen.</font>
<br><font size=3 face="Times New Roman"> </font>
<br><font size=2 face="Arial">Firstly, does anyone have any thoughts on this. Debug ideas etc?</font>
<br><font size=2 face="Arial">Secondly, when the connection to the app server fails it takes forever (minutes) to return no matter what I set the socket connection timeout to.</font>
<br><font size=3 face="Times New Roman"> </font>
<br><font size=2 face="Arial">Thanks</font>
<br><font size=3 face="Times New Roman"> </font>
<br><font size=2 face="Arial">Stacey</font>
<br><font size=3 face="Times New Roman"> </font>
<br><font size=2 face="Courier New">Stacey Verner Ph: +64-9-4154790<br>
Software Developer Fax: +64-9-4154791<br>
DDI: +64-9-4154797<br>
CJN Technologies Ltd. Email: </font><a href=mailto:stacey@cjntech.co.nz><font size=2 color=blue face="Courier New"><u>stacey@cjntech.co.nz</u></font></a><font size=2 face="Courier New"><br>
PO Box 302-278, North Harbour, Auckland 1330, New Zealand<br>
12 Piermark Drive, North Harbour, Auckland, New Zealand<br>
Visit our website at </font><a href=http://www.cjntech.co.nz/><font size=2 color=blue face="Courier New"><u>http://www.cjntech.co.nz/</u></font></a><font size=2 face="Courier New"> </font>
<br><font size=3 face="Times New Roman"> </font><font size=2 face="Courier New">_______________________________________________<br>
Delphi mailing list<br>
Delphi@ns3.123.co.nz<br>
http://ns3.123.co.nz/mailman/listinfo/delphi<br>
</font>
<br>
<br></ul></ul></ul></ul>
<HR><STRONG><FONT COLOR=#ff0000>
Attention: </FONT></STRONG><BR>
Disclaimer:
<P>The information in this electronic mail message is confidential and may be
legally privileged. It is intended solely for the addressee. Access to this
Internet electronic mail message by anyone else is unauthorised. </P>
<P>If you are not the intended recipient, any disclosure, copying, distribution
or any action taken or omitted to be taken in reliance on it is prohibited and
may be unlawful. <BR>If you have received this e-mail by mistake please
call the sender immediately on 09 415 4747 and erase the original message and
any attachments.</P>
<P>Cellular Cellnet (NZ) Ltd accepts no responsibility for any
effects this email message or attachments has on the recipient network
or computer system.
<HR>
<P></P>