What do you feel when random people from your past suddenly message after years of no contact? Do you respond? or just ignore?

Unless there was some really good reason to be suspicious, I'd be curious enough to want to find out why they were reconnecting that I'd respond.

I've done the same when I stumbled across someone I haven't talked to in ages.

Most of the time in the last few years, it's been either because they were looking for work or because they had work they thought I might be interested in.