APM Kerberos and IE9 with caching disabled
BIG-IP 11.3.0 HF6, Working APM and LTM.
Hi,
Has anyone encountered any slow processing issues when using APM with a Kerberos Authentication policy fronting a web app (APM+LTM Mode with a single pool member) when the caching settings in Internet Explorer 9 (Internet options > Browsing History > Settings > Temporary Internet Files > Check for newer versions of stored pages) are set to "Every time I visit the webpage"?
I am not using a HTTP Acceleration profile, just a pretty standard HTTP profile.
If I disable the APM policy and have the setting in IE9 set to "Every time I visit the webpage" it performs normally.
If I enable the APM policy and have the setting in IE9 set to "Automatic" it performs normally.
I only have an issue if both APM is processing the request and IE9 is set to "Every time I visit the webpage".
I have run traces and worked out that the "Every time I visit the webpage" setting in IE9 inserts the following two headers:
If-Modified-Since: "Date+Time"
If-None-Match: "Etag value"
The server is then forced to respond with "304 Not Modified" or a "200 OK".
The other only odd thing that I notice is that with just 7 HTTP GET requests I see 400 DNS lookups been made to the domain controllers for the SPN A and PTR records (which return the correct answer).
Thanks.