topic Re: some problems about VA7400 in Disk Enclosures

some problems about VA7400

darren_11 — Tue, 29 Jan 2002 12:19:26 GMT

1.The oringinal configuration is only a VA7400 disk array,if I add on a disk system with 15 disks, what is the behavior of the array? auto balance or ...

2.If I use raid 5dp with 105 disks that how many disks will be a gorup in other words how many disks fail that the data will lost

3.The disk array is a 7 enclosures configuration if there is a enclosure bad(for example backplane bad),is the data lost?

Re: some problems about VA7400

Enes Dizdarevic — Tue, 29 Jan 2002 15:37:56 GMT

1. "Autobalance", yes. When you add new disks VA will spred existing luns across all the physical disks.
2. VA7400 has two redudancy groups. Disks in odd slots are in one group, disks in even slots in another. Every redudancy group use 2 disk for parity in raid5dp. With 105 disks you can have 7x7=49 disks in one group and 8x7=56 disks in another. You can loose 2 disks in each group without loosing data.
3. If you loose whole enclosure (very unlikely because enclosure has redudant components: two power supplies, two LLC's, every disk is connected to FC loops) you will loose you data because you will loose 7 disks from one group and 8 from another.

Re: some problems about VA7400

darren_11 — Wed, 30 Jan 2002 03:49:27 GMT

Very appreciate