Apache :: Modified Excel Sheet In Docroot Is Taking Time To Reflect It

We have many webservers in our environment, Few webservers serves static contents. In one application, we often change the excel file. Every day or 2 days once we will modified the excel sheet content. File name will be the same, only the content will be changed. We will modify the content of the sheet and upload through FTP to the docroot. After we done this if we access the application URL, its displaying the old content. Its takes time to reflect. sometime with in 3 hours sometimes after a day only reflecting. We are not sure what is the issue. we cleared the cache in browser and tried then also its showing the old content. We are using DNS,network load balancer, proxy between the browser and the webserver.

I tired accessing through FQDN, it showed old content, then i accessed through the LB IP it showed the modifed file. For testing i changed the content again and then accessed. This time even for IP it showed old content. Same i tried with the instance 1 IP and Instance 2 IP. On first time it showing properly but after i cahnged the file content and accessed it showing the old file I tried accesing from a different PC where we havent accessed before, there also it showed old content, SO i feel browser cache is not an issue.

We using Source subnet mask IP persistence in load balancer. I am not sure where the old file is cached actually. Will it be cached in Load balancer or proxy or somewhere in webserver. Just we are placing the file in docroot and accessing it in the URL