Re: "abandoned IT assets"
Different viewpoints on this
1). I’ve seen networks with thousands of building management assets spread over hundreds of sites that no one looks at, fell between the cracks of differing teams, all on the network all running out of date code that could be upgraded but no one is responsible for them.
2). In different jobs I’ve come across switches that have been running in excess of 10 years, typically Cisco and 6500 series chassis,
3). Staff churn, I did an audit a few jobs back and found some stuff running in a paid for dc that everyone thought was turned off years before. Stuff was still on an asset register & customer still paid for it, very low traffic volumes as was basically heart beats, cdp, broadcasts etc etc. I couldn’t turn it off as in theory the customer still needed it but I couldn’t find anyone that was using it. Account is with a different outsourcer now, assets are likely still on a register, still being paid for and likely no one knows what’s it’s for but who cares when your being paid for it?
4). Too big to fail, important switches at the heart of the operation, hundreds of interfaces lots of vrf’s and routing domains. You can’t just drop in a replacement but must migrate onto new tin slowly, unpicking the old and moving addressing over all the while maintaining connectivity.
If you only have a few systems to manage it’s a no brained, I’d even put in MAC learning to stop people bringing in their own hubs (can you buy hubs anymore) or switches, larger environments with lots of network admins must operate differently 802.1x helps but can be a pain.