What is a hot spare and how does it work? The ZFS hot spares feature enables you to identify disks that can be used to replace a failed or faulted device in one or more storage pools. Designating a device as a hot spare means that the device is not an active device in a pool, but if an active device in the pool fails, the hot spare automatically replaces the failed device. You can designate devices as hot spares with the zpool create command when you are creating a pool or with the zpool add … [Read more...] about Solaris ZFS : How to Designate Hot Spares in a Storage Pool
ZFS
Solaris ZFS : How to Offline / Online / Detach / Replace device in a storage pool
Taking Devices Offline in a Storage Pool When hardware is unreliable or not functioning properly, ZFS continues to read or write data to the device, assuming that the condition is only temporary. If the condition is not temporary, you can instruct ZFS to ignore the device by taking it offline. You can take a device offline by using the zpool offline command followed by the pool name and the device name. In the code example in the slide, the c1t0d0 device is taken offline. This device is located … [Read more...] about Solaris ZFS : How to Offline / Online / Detach / Replace device in a storage pool
Solaris ZFS : How to Create and Manage Mirrored Storage Pools
Creating a Mirrored Storage Pool To create a mirrored storage pool, you use the zpool create command followed by the pool name, the mirror keyword, and the storage devices that will compose the mirror. Multiple mirrors can be specified by repeating the mirror keyword on the command line. # zpool create datapool c1t0d0 c2t0d0 mirror c3t0d0 c4t0d0 The command shown in the example creates a pool called datapool with two 2-way mirrors. The first mirror contains the devices c1t0d0 and c2t0d0, … [Read more...] about Solaris ZFS : How to Create and Manage Mirrored Storage Pools
How To Increase rpool Size On Solaris 11 (Requires a Reboot)
With Solaris 11, Oracle introduces the new zpool split command to split the ZFS pool (SPARC / x86 ). This comes in handy to increase the size of the rpool. Below are the high level steps involved : Steps Involved attach a mirror device to the rpool reboot off the mirror (to verify everything works). split the original disk from the pool. set the "autoexpand" property of the rpool Detailed procedure 1. Assuming that your initial rpool has the disk c0t0d0s0 and that you have a new … [Read more...] about How To Increase rpool Size On Solaris 11 (Requires a Reboot)
How To Delete Files on a ZFS Filesystem that is 100% Full
When a ZFS file system has no space left then the deletion of files can fail with "disk quota exceeded". The post provides different ways to create free space to overcome the situation. 1. Truncating files If the files can not be removed directly, we can first truncate them and then delete them. # cat /dev/null > /file/to/delete # rm /file/to/delete Alternatives: there are other options to free up space in the zpool, e.g. 1. increase the quota if there is space in the zpool left 2. … [Read more...] about How To Delete Files on a ZFS Filesystem that is 100% Full
How to check zpool status in Solaris
The post describes few basic commands to check the health of a ZFS pool. 1. Basic Storage Pool Health Status The simplest way to request a quick overview of pool health status by zpool status -x command. Example: # zpool status -x all pools are healthy You can list the pool state for a specific pool by specifying the pool name as follows: Example: # zpool status -x tank pool 'tank' is healthy 2. Detailed Health Status You can request a more detailed health summary by using the … [Read more...] about How to check zpool status in Solaris
How to find zpool version and filesystem version in Solaris
Upgrading the ZFS filesystem and zpool versions is a one-way operation. Once upgraded, the versions cannot be downgraded. This will prevent booting from older boot environments if support for the upgraded zpool/filesystem version is not available within those boot environments. Thus it is important to chcek the zpool version before the upgrade. The current zpool version can be checked with either of the following commands: # zpool upgrade # zpool get version [zpool name] For example: # … [Read more...] about How to find zpool version and filesystem version in Solaris
Solaris ZFS : How to import 2 pools that have the same names
It is possible that you may have to manage 2 pools that have the same name. For example, if you have a pool name "datapool" and you have another from some other storage array called "datapool". You may wish to import this second pool (with the same name) to your system. ZFS will not allow the system to have 2 pools with the same name. Therefore we have to rename one of the pool to some other name. There are 2 scenarios when importing pools with same name. 1. One pool is already imported 2. … [Read more...] about Solaris ZFS : How to import 2 pools that have the same names
How to install a ZFS boot block in solaris
The post discusses about how to install ZFS boot block on a system running a ZFS root filesystem. This is normally required when a system fails to boot from a disk containing a root filesystem. A typical error may include: The file just loaded does not appear to be executable Bootblk: can't find the boot program. Solution Boot from DVD/network/failsafe image In order to install a new ZFS boot block, you need to first boot from DVD, network or the failsafe image on the system. ok> boot … [Read more...] about How to install a ZFS boot block in solaris
How to mount the zfs rpool while booted from CD [SPARC]
To be able to troubleshoot booting issues, sometimes we have to boot the system in single user mode using the CDROM. This is required to access the root file system and find out the issue causing the boot problem. This post describes how to boot using CDROM and mount a zfs root file system (rpool). 1. Boot the system from a CDROM in single user mode. ok boot cdrom -s Boot device: /pci@8,700000/scsi@1/disk@6,0:f File and args: -s SunOS[TM] Release 5.10 Version Generic_137137-09 … [Read more...] about How to mount the zfs rpool while booted from CD [SPARC]