I don't understand how BRPOPLPUSH helps you doing things you could not do with centralized syslog: you can also start indexing things with syslog by analysing t

I don't understand how BRPOPLPUSH helps you doing things you could not do with centralized syslog: you can also start indexing things with syslog by analysing the central logs without changing anything client-side. And in both cases, what will be needed is essentially the same: if the logs are not structured at the source, you will need to post-process them, the storage medium does not change any of that. The redis is easier than syslog is a bit of a strawman, because you will have to understand syslog anyway, since that's the only thing spoken by quite a few applications. In the OP'case, they are already using redis, so the cost on that side is very low, though.