Recent content by llowrey

Can't go wrong with Kaiam QSFP+40G-LR4 Lite for under $10. These are low power (hence 'Lite') so you're not going to be able to reach the building down the street with them. https://www.ebay.com/itm/405787650383

I can confirm both Arista and Cisco BiDi with CX4 Lx and SX6018. The SX6036 will work, assuming you're run the fae command. The stock firmware only allows high-power modules on certain ports. If you're running my modified firmware then you should be able to run high-power on all ports. But, a...

Yep, I can confirm both the Cisco and Arista bidi modules do not work with CX3 cards. They do work with my CX4 Lx cards that are connected to my SX6018.

I have found that data retention, even with TLC and keeping the power on, isn't perfect. The periodic background scans that are supposed to happen haven't been good enough for me and I started finding occasional bad blocks during btrfs scrubs. I added a monthly scrub and have not had a bad block...

Yes. The modded firmware removes the power restriction on all ports. That, combined with the above command enables LR4 optics on all ports. I don't want to publish the firmware publicly since there is some risk so feel free to DM me and I'll send you the info. More than a dozen people have used...

There's only 3 left at the first listing, which is the seller I bought from, but it's a good price for these modules. I can't vouch for the modules from the second seller. These are LC BiDi 40G modules that work with both MMF and SMF (can confirm). Moreover, with SMF, they also work when paired...

This one is more expensive when you factor shipping to the US, $74 vs $21. Other than that, seems like the same hardware.

The manuals have block diagrams which show how the lanes are connected

After doing an absurd amount of testing to reduce variables, I'm left with my problems likely being due to the type of SAS connector on the backplanes. This Norco chassis has 5 separate passive backplanes. All five are identical, except, two boards have SAS connectors that are different from...

Good suggestion. I put one SATA back in the chassis and it only negotiated 3Gbps (SATA Version is: SATA 3.1, 6.0 Gb/s (current: 3.0 Gb/s)) Interestingly, the SAS drives all negotiated 12Gbps even though the links are not completely reliable.

In the case of the SAS drives it's: sd 33:0:155:0: [sdaa] tag#2242 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s sd 33:0:155:0: [sdaa] tag#2242 Sense Key : Aborted Command [current] [descriptor] sd 33:0:155:0: [sdaa] tag#2242 Add. Sense: Ack/nak timeout sd 33:0:155:0: [sdaa]...

The chassis in question is at the end of a daisy-chain with one JBOD in the middle. External cables are 2m [hba -> 0.5m -> expander] -> 2m -> [ expander ] ->2m -> [ expander -> 0.75m -> sas/sata drive] So, the max signal-lenghth is 2m and at SAS signaling and 0.75m at SATA signaling.

internal cables were all either 0.5m or 0.75m

I recently acquired a second hand (at least!) chassis with SAS backplanes. I've been having a ton of trouble with it. I first put in a bunch of old SATA drives but they all were constantly erroring and when the did work, they were unusually slow. I then swapped them out and put in 12g SAS drives...

My ASRock Rack EPYCD8 gave up the ghost and I replaced it with a ROMED8-2T. After replacing the motherboard I can't get SR-IOV working for my CX-4. It used to work just fine. The only difference is the motherboard, everything else is unchanged. SR-IOV works just fine for the onboard Intel...