Hi everybody, I am facing a problem which I cannot solve in a satisfying way and after searching the known resources for a while I wonder if anyone has ever solved a similiar one. Let me first describe the situation I have here. I am using a reverse proxy installation to access a backend server transparently. However, there are in fact two backend machines instead of one and they are configured in a cold stand-by way meaning only one is ever running. Additionally there is a special dns-resolver which supplies the ip address of only one of the backend machines depending on which one is running at the moment during DNS name resolving. This works perfectly as I can check each time after the switch-over with a simple nslookup command. The definition of the reverse proxy clause is like this: NameVirtualHost 192.168.100.10:443 <VirtualHost 192.168.100.10:443> SSLEngine ON SSLProxyEngine ON ProxyPass / https://backend.mydomain.com:8080/ ProxyPassReverse / https://backend.mydomain.com:8080/ </VirtualHost> Where 192.168.100.10 is the address of the reverse proxy machine and the fully qualified name of backend.mydomain.com is the logical name of the service which the dns-resolver resolves to either one of the backend servers depending on their run status. When I access the backend service over the reverse proxy the Apache server running as the reverse proxy caches the IP address of the then running backend server. Now if I switch the servers, shutting one down and bringing the other up and updating the dns-resolver, I can see that the dns-resolving mechanism works but the reverse proxy still uses the cached IP address of the now defunct backend server. I have tried to tackle the problem by supplying some parameters to the ProxyPass clause. While setting the option disablereuse=On helps to avoid the caching problem, this is not really an option because it massively degrades the performance during peak times. Thus I tried the expiry option by setting smax=0 ttl=30. I would have expected that this would expire all connections after they were idle for 30 seconds which would be fine. But this seems not to work. I have found a corresponding Bug #43371 where the possibility to set smax to zero was enabled by a patch in the first place. I have analysed the solution and have found no error with this patch. Nevertheless I think there still might be a problem with this since some of the requests (But not all!) are still using the "old" IP address. Has anyone of you ever had a similiar problem of chached DNS-resolved IP addresses? Have you found any satisfactory solution? Any additional clues for me? Any help would be greatly welcome. Regards Slawo --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx