3 ms·

I've returned faulty RAM after confirming a suspicion using MemTest86 (the PassMark one), several times over the years. In that situation, it's so nice to actu

I've returned faulty RAM after confirming a suspicion using MemTest86 (the PassMark one), several times over the years. In that situation, it's so nice to actually have some evidence to point to (a photo of the test results screen).

linsomniac 4y ago
Memtest is awesome, I've used it for decades and run it on every new machine I get. It's great at detecting memory, bus, and CPU problems. We had a Dell R640 rackmount that arrived and part of our burn-in testing is running memtest, which said one of the modules had a problem. I contacted Dell support and they had me run the Dell built in memory test, which IIRC took something less than an hour. Memtest was taking around a day to generate this error. Dell support didn't want to replace it because their built in test wasn't showing anything. This was maybe the 5th or 6th same model server we had gotten and all of them were clean, so I really didn't want to put this into production. Could have been a memory problem, could have been CPU or motherboard issue... Went back and forth a few times, and finally contacted our sales person asking them what our return window was for the server. They reached out to support, who contacted us and said "Fine, we'll send you a replacement, but only this one time!" Usually I've gotten really good support from Dell Pro Support, but this time I was pretty disappointed.
- booi 4y ago
  This is why I rarely ever bought dell pro support. It's easier to take the savings and buy an additional unit if anything ever goes wrong (assuming you buy enough machines to make this economical). After a while you really don't need dell support to help and it's cheaper and faster to just replace the ram/drive/backplane/server.
  - linsomniac 4y ago
    This. This is what I did when I had ~100 servers, mostly lower end Supermicro, just buy an extra unit. But now I have ~20 higher end Dell boxes ($13K), and the pro support makes more sense, especially since maybe only a third of them are on support. I used to buy a couple machines a month, now I'm buying a machine or two a year. As I said, Pro Support has been fantastic for every other issue I've had, it was just this one memory issue. For comparison, a couple years ago we had a machine in production that system load went crazy on, 300-400 in "uptime". Nothing was really goning on on the machine. I ended up with 2-3 engineers helping me out as the path of the sun moved me into different support regions. They couldn't pin it down to any specific thing, but ended up replacing a couple SSDs, the RAID card, and the backplane. I'm pretty sure it was the LiteOn SSDs soiling the sheets, but that's what they ended up doing and we've been good since then.
    - sitkack 4y ago
      Supermicro was 1/2 to 1/3 of what HPE was, ops ended up going with HP. But we could have had a Hadoop cluster that was 2-3x larger for the same money and required less support. Just power down the hosts that develop hardware issues, which is frankly pretty rare.
- Beltalowda 4y ago
  When I was dealing with a lot of hardware my general strategy to deal with these sort of problems was to just lie. Look up what error code it gives on bad memory and tell them that. Invent an error code. Tell them the diagnostics are freezing. Tell them the machine doesn't even start and gives a "bad memory" error. Whatever.

linsomniac 4y ago

Memtest is awesome, I've used it for decades and run it on every new machine I get. It's great at detecting memory, bus, and CPU problems. We had a Dell R640 rackmount that arrived and part of our burn-in testing is running memtest, which said one of the modules had a problem. I contacted Dell support and they had me run the Dell built in memory test, which IIRC took something less than an hour. Memtest was taking around a day to generate this error. Dell support didn't want to replace it because their built in test wasn't showing anything. This was maybe the 5th or 6th same model server we had gotten and all of them were clean, so I really didn't want to put this into production. Could have been a memory problem, could have been CPU or motherboard issue... Went back and forth a few times, and finally contacted our sales person asking them what our return window was for the server. They reached out to support, who contacted us and said "Fine, we'll send you a replacement, but only this one time!" Usually I've gotten really good support from Dell Pro Support, but this time I was pretty disappointed.

booi 4y ago
This is why I rarely ever bought dell pro support. It's easier to take the savings and buy an additional unit if anything ever goes wrong (assuming you buy enough machines to make this economical). After a while you really don't need dell support to help and it's cheaper and faster to just replace the ram/drive/backplane/server.
- linsomniac 4y ago
  This. This is what I did when I had ~100 servers, mostly lower end Supermicro, just buy an extra unit. But now I have ~20 higher end Dell boxes ($13K), and the pro support makes more sense, especially since maybe only a third of them are on support. I used to buy a couple machines a month, now I'm buying a machine or two a year. As I said, Pro Support has been fantastic for every other issue I've had, it was just this one memory issue. For comparison, a couple years ago we had a machine in production that system load went crazy on, 300-400 in "uptime". Nothing was really goning on on the machine. I ended up with 2-3 engineers helping me out as the path of the sun moved me into different support regions. They couldn't pin it down to any specific thing, but ended up replacing a couple SSDs, the RAID card, and the backplane. I'm pretty sure it was the LiteOn SSDs soiling the sheets, but that's what they ended up doing and we've been good since then.
  - sitkack 4y ago
    Supermicro was 1/2 to 1/3 of what HPE was, ops ended up going with HP. But we could have had a Hadoop cluster that was 2-3x larger for the same money and required less support. Just power down the hosts that develop hardware issues, which is frankly pretty rare.
Beltalowda 4y ago
When I was dealing with a lot of hardware my general strategy to deal with these sort of problems was to just lie. Look up what error code it gives on bad memory and tell them that. Invent an error code. Tell them the diagnostics are freezing. Tell them the machine doesn't even start and gives a "bad memory" error. Whatever.