I’ve wrestled with this question for a while. There are a number of factors determining how many disks should go into a RAID5 array. I don’t know the HP 2012i, so here is my generic advice for RAID5: Non-recoverable read error rate: When a non-recoverable read error occurs, that read fails. For a healthy RAID5 … Read more
Your plan is not nuts. As usual, there’s more than a few ways to attack this based on what you’re trying to achieve and how to protect your data. First up, you can present a raw LUN to a VM using a “Raw Device Mapping”. To do this: Present the LUN to the ESXi host … Read more
FWIW I have experience with up to 92 disks in a single ZFS pool and so far it works fine. But if you’re really talking about several hundreds of disks I would consider partitioning them into a small number of disjunct (but still large) pools. I don’t want to know how long e.g. a zpool … Read more
Most systems I’ve seen attempt to map the IP ranges to a hierarchy of geography and/or system components. One employer tended to use: 10.building.floor.device (with non-user resource VLANs using 10.x.100.x to 10.x.120.x) and 10.major_system.tier_or_subsystem.component
I hope this is gonna help a little. I tried to not let it turn into a full wall of text. 🙂 3Par/Isilon If you can and will dedicate a fixed amount of man-hours for someone who takes the SAN admin role and wanna enjoy a painless life with night-sleep instead of night-work then this … Read more
I’m not at all surprised. SAN arrays typically have a LOT of disks involved. The limiting factor for disk I/O is the speed of the individual disk, and these stack. 6 drives locally in a RAID10 will perform better than 2, and 80 drives on a SAN will perform better than 10 drives locally. There … Read more
Consider whether you really need hot failover. If you’re worrying about price at the level of an entry level SAN then consider whether you really have a business case for that recovery model. How expensive is your downtime for an outage? If the cost of an outage justifies the cost of a decent SAN, buy … Read more
I do a lot of VMware consulting work and I’d say that the percentages are closer to 80% of the installed base use high availability shared storage (FC, iSCSI or high end NAS) and a lot of my clients are SME’s. The key factor that I’ve found is whether the business treats its server up … Read more
Fibre Channel switches usually connect clients to storage. FC is a protocol that is designed explicitly to transport SCSI commands. In fact, the Fibre Channel protocol is a direct extension of the SCSI protocol. All SCSI commands have a FC equivalent, and FC has a few extra ones that allow for networking. Assuming you have … Read more
Logs and data drives have different data access patterns that are in conflict with each other (at least in theory) when they share a drive. Log Writes Log access consists of a very large number of small sequential writes. Somewhat simplistically, DB logs are ring buffers containing a list of instructions to write data items … Read more