Gigabit Ethernet Experiments

Today I got the Gigabit Ethernet equipment I ordered: A Netgear GS605 5-port switch a Linksys LKG-6100 networking card for “vector” (both “scalar” and “manifold” are already Gigabit Ethernet-ready), and some new Cat 6 cables too, because the cables I used were way too long. They were from my dorm days when the Ethernet port was somewhere far away.

I took out the Siemens 5-port switch and replaced it with the Netgear one. I removed the old SMC 100 Mbit card from “vector” and put the Linksys card in. I replaced all the long, old, twisted Cat 5 cables with nice, new Cat 6 cables, and connected the Netgear switch to my DSL router. And it seemed to work! All computers were reporting 1000 Mbit network connections.

However, when I tried to copy some large files between the “scalar” and “vector”, it seemed like the transmission was happening at only 1 Mbit. That was a little slow. I also couldn’t connect to the web server on “vector”.

After a while, I figured out that the web server problem was just the DSL router firewall. Since I had changed network cards, I needed to reconfigure the firewall. And the slow transmission was due to a huge number of hardware interrupts on “vector”, probably caused by the primary hard drive, a 120 GB Maxtor (not the one that was failing yesterday; that was the 80 GB Maxtor), was running in PIO mode instead of DMA (@Update: Using this neat registry hack, I was able to revert the 120 GB Maxtor to DMA mode.@). When I transferred from a hard drive that was running in DMA mode, or when I was copying between “scalar” and “manifold”, I got the transmission rate I expected.

So, I think my Gigabit Ethernet setup works, my primary hard drive on “vector” just blows. Maybe I’ll have to replace it. Or considering that I had the other Maxtor crap out yesterday, I should replace both of them with one drive, e.g. a Seagate Barracuda 7200.10 250GB for $65 plus shipping and tax.

So… New hard drive? NAS? Both? (@Update: Because both Maxtors started to flake out — the 80 GB one disappeared completely, even though the cables are brand new and rounded, and the 120 GB one was extremely slow — I’ve decided to buy a 250 GB Seagate for $55 after S/H and tax. It’ll replace both Maxtors, and the 120 GB Maxtor will go into a mobile rack, either by replacing the current 20 GB drive in it, or by getting another rack for $10. Or I could get two new racks and then have a 160 GB, a 120 GB, an 80 GB and a 20 GB hard drive in mobile racks… But what good is that if I can’t rely on the 120 GB and the 80 GB drives? The reliability was the reason I bought the new Seagate drive.@)


About Mathias

Software development engineer. Principal developer of DrJava. Recent Ph.D. graduate from the Department of Computer Science at Rice University.
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