topic BSAS vs FSAS in ONTAP Discussions

BSAS vs FSAS

MohamedShehata — Wed, 04 Jun 2025 10:08:39 GMT

Hello all,

what is the difference between BSAS and FSAS disks ? and can both disk types become in one aggregate ?

NetApp version: NetApp Release 9.3P18

Model: FAS2554

Re: BSAS vs FSAS

Ontapforrum — Thu, 18 Nov 2021 12:45:55 GMT

BSAS: High Capacity SATA disks plugged-in-to SAS Shelf using "additional hardware" and hence called Bridged-SAS

FSAS: High-capacity (Fat) Serial Attached SCSI disks

https://library.netapp.com/ecmdocs/ECMP1368859/html/GUID-B57DC254-3A78-43EE-ADF7-8ACF0DC76761.html

You should be able to mix:
https://docs.netapp.com/ontap-9/index.jsp?topic=%2Fcom.netapp.doc.dot-cm-cmpr-920%2FTOC__storage__raid-options.html
raid.mix.hdd.disktype.capacity = Controls mixing of SATA, BSAS, FSAS and ATA disk types. The default value is on, which allows mixing.

Re: BSAS vs FSAS

paul_stejskal — Thu, 18 Nov 2021 13:58:20 GMT

I believe they are also an inch smaller. FSAS have a slightly larger performance window but the biggest difference to me is the response times are so much better. BSAS is just so slow it is bad, but FSAS is decent for spinning rust.