Load Balancer Query

[CMCN1982]

In our Stage environment we have  a two server cluster and since we upgraded to version 14.2 we have noticed some issues which CA have attributed to the fact that we use a load balancer.

 

 

One of the issues we see is that when a user access the environment via the URL.

He logs in and goes to Portfolios

Within any of his portfolios he clicks the Waterlines tab.

Here, where usually he can see the icons available to manipulate the portfolio, they are missing.

 

 

However, when investigating I tried accessing the application by directly accessing either of the tomcat instances e.g. http://server1:8080

When I do this and replicate the steps, I CAN see the icons as expected.

 

 

CA advised to check the load balancer settings we have in place in comparison to the release notes for 14.2 and to me, they do look to be ok. e.g. session persistence enabled.

 

 

We are using ARR in IIS on Windows Server 2008 R2.

 

 

Can anyone offer any insight?

[Andrew LERNER]

When trying to access the page via the load balancer, can you see any 404 errors in your browser's Developer Tools - Network view? Are there any js errors in the console?

[CMCN1982]

I can't see any network errors in relation to the icons not displaying.

I have a scheduled outage tomorrow morning to fix another issue so I am going to try resetting IIS to see if this helps.

[Suman Pramanik]

Hi Colin,

 

It's not network errors but something which is blocked by the load balancer, so if you do a trace with load balancer and without load balancer and you will be able to see the difference.

 

Regards

Suman Pramanik

[Andrew LERNER]

But if the LB was blocking something, you should still see that manifested as some sort of 404 type error within the browser.

[CMCN1982]

It's strange, when I hover over the areas where the icons should display an descriptive box appears showing what the missing icon performs if clicked. Indeed, if I do click on it, the action performs as expected. e.g. Show/Hide Totals

 

If I right click on the missing icon and select properties I see that it is just an image - address: URL/niku/ui/uitk/images/s.gif

[Suman Pramanik]

Did you try Andrew suggestion to check for 404 type errors.

[CMCN1982]

I am going to install Fiddler Trace now and compare with load balancer and without load balancer

[Andrew LERNER]

The image that has the icons is ui/uitk/images/odf.png.

 

I have a feeling that IIS doesn't like the parent path (..) for the icons image (and s.gif probably): ui/evolution3/{color:red}..{color}/uitk/images/odf.png

Can you (or your loadbalancing team) enable failed request tracing?

Using Failed Request Tracing Rules to Troubleshoot Application Request Routing (ARR) : The Official Microsoft IIS Site

[CMCN1982]

Thank you Andrew.

We have Failed Request Tracing enabled already but it was limited to 50 log files.

When I checked our log file location it was full so I have deleted the old 50 entries.

 

I will replicate the steps to see if anything is generated and I'm also sifting through both Fiddler traces to see if can see anything that stands out.

[CMCN1982]

Ok, so I have replicated steps and I'm not getting any log files generated in my failed requests trace folder.

I have created two trace files, one with load balancer & one without.

 

Suman - I have just emailed you the results. I cannot see anything which suggests the reasons for the icons not displaying via the LB. Perhaps you might see something I have misseD?

 

Thanks guys.

[Andrew LERNER]

what happens if you paste the following in your browser:

 

(add an 's' to the protocol if you're using ssl)

{noformat}http://<server>/niku/ui/evolution3/../uitk/images/odf.png{noformat}

and

{noformat}http://<loadbalancer>/niku/ui/evolution3/../uitk/images/odf.png{noformat}

[CMCN1982]

With some assistance from a colleague we have resolved the issue:

 

"Save Changes"  image

<img border="0" src="ui/evolution3/../uitk/images/s.gif" style="background: url('ui/evolution3/../uitk/images/odf.png') no-repeat scroll -1650px 0px transparent; width: 16px; height: 16px; position: relative; top: 0px; left: 0px;" __w="img" __n="PFM_SAVE" onclick="handleEvent('onclick','pfmSave')" alt="Save" title="Save">

 

 

"Discard Changes" image

<img border="0" src="ui/evolution3/../uitk/images/s.gif" style="background: url('ui/evolution3/../uitk/images/wbs.png') no-repeat scroll -160px 0px transparent; width: 16px; height: 16px; position: relative; top: 0px; left: 0px;" __w="img" __n="PFM_DISCARD_CHANGES" onclick="handleEvent('onclick','pfmDiscardEdits')" alt="Discard Changes" title="Discard Changes" class="caui-image-disabled ppm_image_disabled">

 

Looking at the odf.png image coming back through Firebug on the URL shows the image as being 1603 x 20px in size, while on Tomcat URL its showing as 1798 x 20px so

CSS for the Save Changes image is set as being -1650px as its starting point - this is outside the dimensions of the image coming through so that's why the buttons are not displaying.

 

So on the application server's IIS and under ARR, we removed the cache object for - Delete Specific Cached Objects - https:/URL.com/niku/ui/uitk/images/odf.png - and the image is now appearing correctly for us.

 

The ARR caching option is a performance enhancement and is not crucial to functionality so a clear of all cache objects can be ran as part of our Production upgrade.

 

Thanks for the tips and advice though. Appreciated!