Maintenance Page using irule

That isn't going to work. Your best bet is to add your HTML page as an iFile:

https://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/ltm-implementations-11-5-0/27.html?sr=47873155

https://devcentral.f5.com/wiki/iRules.iFile.ashx

Then your iRule might look something like this:

when HTTP_REQUEST {
     Retrieve the file contents, send it in an HTTP 200 response and clear the temporary variable
    set ifileContent [ifile get "/Common/iFile-index.html"]
    HTTP::respond 200 content $ifileContent
    unset ifileContent
}

Hi Kevin, Thanks for the reply.

LB is running with the version 10.2.1. Will ii support iFile ? Also i will go through the link which you have suggested and come back to you.

No option in 10.2.1 for iFile. Pleas help

Hi Kevin, Thanks for the reply. Could you please help me with the second option ? I am new to irule and sorry for asking you again and again in detail.

I have attached the sample image as well.

Here's a few resources to get you started.

https://devcentral.f5.com/questions/serve-status-page-with-images-on-ltm-v102

https://devcentral.f5.com/codeshare?sid=610

https://devcentral.f5.com/wiki/iRules.LTMMaintenancePage.ashx

the below link seems to be suitable for my requirement :

https://www.fir3net.com/Loadbalancers/F5-BIG-IP/bigip-f5-ltm-sorry-page-with-base64-images.html

But when i tried to create DATA GROUP, i am getting a error message link below :

01070712:3: Caught configuration exception (0), Max string size exceeded during update of attribute:data type:class_string_item max:65520 received:716657 - EdbCompositeObj.cpp, line 84.

Please help me to fix the issue.

How big is the base64-encoded image? You may need to make it smaller (or try a different compressed image format).

Its 524 KB file with 960x500 in size and its in JPEG format

Understood. I think you're going to have to make it MUCH smaller.

Would your organization happen to use a (cloud) CDN? If so you could store the image there.