even though there isn't a consensus on whether it's my local disk, the server's disk, or the network that is causing it.

There is no consensus, because there is simply no way to make that determination based on the information provided. However, there are some simple steps that you can use to help make the determination:

1. Install perl on another drive (preferably another server) and share it.

   If the problem goes away, it is likely the original drive that's faulty.

2. Try it (from the existing server), from several different clients.

   If it only fails from one client, look to the local disk, or local network configuration.

   If it fails on some and not others, it is unlikely to be either the local or remote disks that are at fault. So look to the network setup. In particular, look for commonalities in the network setup (MTU setting etc.) between those that do fail and those that don't.

   If it fails on all of them, it is unlikely to be local disks. So go to step 1, and retry from the same clients.

3. If it fails on one (or some) subnets and not others.

   Look for problems with the bridge or router between that (those) subnets and the subnet containing the server.

Most of these tests are relatively quick and simple to carry out. If you have a local support guy/team worth their salt, it'll be bread & butter work for them. Fixing the underlying problem will likely benefit your entire setup, not just your Perl installation.