Hello, I would like to receive some help in a project of upgrading a cisco wireless network.
It's a network with 20 AP's 1230 802.11b/g and 5 AP's 1140 802.11n with 1 Cisco WLC 5508 7.0.x and 1 WCS for guest access, monitring and reporting
The project is for replacing the 20 AP's to 802.11ac, upgrading WLC and WCS software and adding redundancy (backup controller) to the solution because at this moment the controller is a single point of failure.
I would start this project with reviewing the usage of the wireless network. So you are going to use 802.11ac, great, but with what requirements in mind? There is a change that those have changed since the current network was deployed. You can do a 1:1 replacement, but I recommend doing a survey with the 2700 access-point and the current (or future) requirements in mind.
If it is just a pricing thing, I would count on 20x 2700 access-points, one AIR-CT5508-25-K9 controller*, a extension of the current smartnetcontract, an upgrade of the WLC software, the configuration changes and a new implementation of Prime infrastructure with enough lifecycle licenses.
*: Instead of buying a new physical WLC with 25 licenses you can also buy a HA WLC. An other option is migrate to a vWLC and buy new AP licenses, but you don't have all the features you have right now so that depends on your current deployment.
You can also buy a 2504 WLC, which scales to 75 access-points and is much cheaper than the 5508. When you buy a 5508 HA WLC, can you create a SSO setup so can only have to do changes on one WLC and have a very fast failover. But that solution is much more expensive.
With the vWLC you leave the physical WLC's behind and move to a VMware based controller. But it depends on your infrastructure / requirements if that is an option.