LSI 92* questions.

I have been looking at LSI 9207-8i cards and in my search, I found similar cards like 9211, 9240, 9260, 9261, 9270 etc... Many models have an -8i at the end and some cards have a battery on them.

What is the deference between the various models?
What does the "8i" mean? Does that just indicate an newer, better version like "Ti" on Nvidia GFX cards?
What is the battery for on some of the cards? Do I need or want it?

The different models have different processing speeds and supported RAID levels or capabilities. the number is how many drives are supported directly by the card without an expander, and the I means the ports are internal (external are on the back of the card to connect to another chassis). The battery is for caching support in case you lose power it retains data stuck in the cache that hasn't been committed and can increase (sometimes significantly based on your workload) your write throughput.

The battery is for battery backed cache. Without the battery, most of them will be stuck in write-through mode which is going to be slower for writes. With it is write-back mode, it waits to do a large write until the cache is full. With write-through mode, it writes immediately.

If you get a 9271 with 1GB of cache, you can also enable cachecade 2.0 which supports both read and write cache via an SSD.

The earlier models with cachecade 1.0 only support read cache with an SSD. Some of the earlier models like the 9265 came in two flavors. 512Mb (which does not allow cachecade), and 1GB which does allow cachecade.

What does the "8i" mean?

Click to expand...

8 SAS 2 ports internal ( 2 x 4 port SFF-8087 connectors)

So I currently have an LSI 9201-16i in my server already. The 8 port version of this card is scarce and none on ebay have the high profile bracket.

It probably wouldn't make much sense to get an 8 port card with a battery since my 16 port card does not have one. What LSI card other than the 9201 is the most like mine? Any suggestions?

From what I read, the 9201 doesn't do hardware RAID, so you must be using it JBOD. Are you also looking for 16 ports, or just 8? This PDF has a comparison chart:

https://docs.broadcom.com/docs/AV00-0315EN

The 9207-8i is similar (only does JBOD), but PCIe 3.0 (which is backward compatible), 8 ports, low profile.

The 9211-8i offers lower end hardware RAID 0, 1 and 10, 8 ports, low profile.

The only thing with the low profile cards is to make sure you get a full-height bracket if you need one. I think the retail packaging ships with both brackets.