CIAO VERSION: 0.5.8<br>TAO VERSION : 1.5.8<br>ACE VERSION : 5.5.8<br><br>HOST MACHINE and OPERATING SYSTEM:<br> i686 pc, SUSE linux Enterprise Server 9, Kernel 2.6.5<br><br>COMPILER NAME AND VERSION (AND PATCHLEVEL):<br>
gcc 3.3.3 (SuSE Linux)<br><br>THE $ACE_ROOT/ace/config.h FILE:<br> #include "config-linux.h"<br><br>THE $ACE_ROOT/include/makeinclude/platform_macros.GNU FILE :<br> include $ACE_ROOT/include/makeinclude/platform-
linux.GNU<br><br>CONTENTS OF $ACE_ROOT/bin/MakeProjectCreator/config/default.features<br> (used by MPC when you generate your own makefiles):<br> N/A<br><br>AREA/CLASS/EXAMPLE AFFECTED:<br> CCM deployment<br><br>
SYNOPSIS:<br> Which possibilities exist to have fault tolerance in CIAO and DAnCE?<br><br>DESCRIPTION:<br>Hi there,<br><br>The basic challenge, this post is about concerns fault tolerant behavior<br>of a system of CCM components. Thus, before becoming too specific:
<br>Does anyone have some experiences with how to implement CCM systems,<br>which have to be very reliable in terms of uptime/availability? <br>What CCM mechanism are there to achieve this?<br><br>To become more specific now:
<br>The following approach is inspired by the CORBA fault tolerance service:<br>The basic idea is, that a group of components (having interdependencies), <br>provides some services which need to have a very high availability.
<br>So all components will be instantiated more than one time to have a redundant backup<br>(keeping these components in sync might be necessary, depending on the component <br>type but this is not in the scope of this question).
<br>If one of these components fails (assuming that there is a way to find out when a component<br>fails ... usually through CORBA exceptions), it will not only be necessary to replace<br>this single component by its backup, but also to inform the whole component group to reconnect
<br>to the correct component.<br><br>Can you give me some advice, how to achieve this using standard CCM mechanisms? <br><br>I think that ReDaC might aim in this direction. <br>Is it possible to dynamically create an assembly file, which reflects the necessary connection
<br>changes to integrate a backup component instead of an unresponsive component? <br>Can you foresee any technical or performance problems, that would conflict with such an approach?<br><br>Besides from technical issues:
<br>ReDaC seems to be a nonstandard enhancement of the CCM spec by DAnCE. <br>Is that correct? <br><br>I ask this, because it's necessary for the project I work with to be based on standards specifications <br>only at this level of the design. So, are there any efforts to standardize the redeployment features?
<br><br>Are there other CCM standard features, I didn't think about, which could provide fault<br>tolerance on component assembly level.<br><br>Thanks for reading all through this rather long explanation and for giving any helpful remarks,
<br>Friedhelm<br>