XtremIO X1 and VMware - APD v’s PDL

In general, when a Storage Controller is shutting down for any reason, XtremIO X1 will send a "Logical Unit Not Supported" SCSI response code (0x5/0x25) in response to any requests received by that storage controller from a connected host. This could be just a single SC shutdown…

#Tags: xtremio, vmware, APD, PDL

XtremIO Snapshots and Veritas Volume Manager

It's been 20 years almost to the day since I started using Veritas Volume Manager, or Sun Enterprise Volume Manager (SEVM) as the re-branded version from Sun was called at the time. SEVM used to be included free with all Sun SPARCstorage Array 110 model arrays (an external proprietary fiber-connected…

#Tags: xtremio, vxvm, snapshot

Using the XtremIO REST API - Part 5

In Part 1 of Using the XtremIO REST API I covered how to access the API, and how to read data from it. Part 2 covered how to create and modify objects, Part 3 covered Snapshots, Part 4 was some Best Practices. Next up is an example using the API…

#Tags: xtremio, restapi, perl

Parsing XtremIO CLI Output

I generally don't recommend people use the XtremIO CLI for programmatic access - it's just so much easier and better to use the REST API. However there are occasions where using the CLI may make sense. Access to the CLI can be automated via SSH, and sending commands is relatively…

#Tags: xtremio, cli

XtremIO and VMware Path Failure Detection

In XtremIO XIOS version 4.0.10 we made an (optional) change to the SCSI error codes that the array returns to ESX hosts under certain circumstances. To understand the difference, we first need to understand a little about how VMware acts when a LUN disappears for some reason. When…

#Tags: xtremio, vmware, APD, PDL

Friends Don't Let Friends Run Oracle on ZFS

I frequently get asked why I recommend against running Oracle DBMS on ZFS, and instead recommend using ASM. The filesystem v's ASM (or filesystem v's raw device) is a decision that people have had to make with databases for dozens of years. Over that time, in general, filesystem performance has…

#Tags: zfs, solaris, alignment, performance testing, xtremio, oracle