Recently, I made an upgrade on some of 6509 switches. I bought totally new 6509-E system including chassis, fan, power, and some new line cards. I also insert my fiber line cards that I used in old 6509 with supervisor 2.
Everything was fine until I checked modules status with “show module” command. Switch was up, new line cards were functioning, but my old WS-X6516-GBIC’s were in PwrDown state. When I checked the switch logs I found

00:02:31: %C6KPWR-SP-4-UNSUPPORTED: unsupported module in slot 2, power not allowed: The image for the card is not bundled in image.

What does it mean? I had a recent IOS and it does not support this card. I was not surprised because it happened to me before. I just checked the software advisor tool from Cisco and found another version.I tried it, but it did not work out.

A wise friend of mine told me that I should give a try to a safe harbor image. I was not aware of safe harbor program until that time. Safe harbor images are tested images. They are stable, interoperable and solid. It was my last chance before I should have to escalate this problem.

I found out that there are some problems between Supervisor Engine 720 and WS-X6516-GBIC, but the problem were only valid for 5.0 to 5.3 Hw versions and I had 5.7. It should not be my problem but text mentioned about DFC Sub-modules. I focused on DFC daughter card then. Everything become clear when I found “Catalyst 6500 Series DFC, DFC3A, DFC3B, and DFC3BXL Installation Note” document. I saw a note mentioned below

Note You cannot have a DFC in a system with a Supervisor Engine 720

I removed one DFC (WS-F6K-DFC) from one of the WS-X6516-GBIC and finally it started to work. I also changed the IOS images to safe harbor ones. I spent days to solve this problem and this turned out to be a simple issue for which I got the answer instantaneously from the web!

All routers including the oldest (e.g. Cisco 2500 series) and smallest (e.g. Cisco 800 series) support NetFlow. Some functions does not exist in older IOS versions.
Catalyst 6500 series switches support NetFlow. Catalyst 4500 series switches support NetFlow with Supervisor IV/V + WS-F4531 Catalyst 4500 NetFlow Services Card.

Standalone or stackable switches do not support NetFlow. This means Catalyst 4948, Catalyst 3750 or Catalyst 3560 series switches do not support NetFlow. You can see the necessary commands on config mode, but they are not effective. It is not about IOS version or feature set. You need a modular switch for NetFlow.

Unfortunately, the answer of “What Cisco switches support netflow?” is only the modular switches.

More than 16 standby groups not supported in this platform.

message.Cisco says that this is a per interface limit. So, you can use same ID in several interfaces.

You can find the details on “HSRP Group Limitation on Catalyst 6500/6000 Series Switches Frequently Asked Questions”