>I went back and dug through some of my email, and the issue showed up as
>That was fixed in b77 and s10 update 6.
>I looked at this CR, forgive me but I am not a ZFS engineer. Can you explain
>in, >simple terms, how ZFS now reacts to this? If it does not panic how does
>it insure >data is save?
Found some conflicting information
Infodoc: 211349 Solaris[TM] ZFS & Write Failure.
"ZFS will handle the drive failures gracefully as part of the BUG 6322646 fix
in the case of non-redundant configurations by degrading the pool instead of
initiating a system panic with the help of Solaris[TM] FMA framework."
>From Richards post above.
"NB definitions of the pool states, including "degraded" are in the
>From zpool man page located below.
"Device Failure and Recovery
ZFS supports a rich set of mechanisms for handling device failure and
data corruption. All metadata and data is checksummed, and ZFS automatically
repairs bad data from a good copy when corruption is detected.
In order to take advantage of these features, a pool must make use of
some form of redundancy, using either mirrored or raidz groups. While ZFS
supports running in a non-redundant configuration, where each root vdev is
simply a disk or file, this is strongly discouraged. A single case of bit
corruption can render some or all of your data unavailable.
A pool's health status is described by one of three states: online,
degraded, or faulted. An online pool has all devices operating normally. A
degraded pool is one in which one or more devices have failed, but the data is
still available due to a redundant configuration. A faulted pool has corrupted
metadata, or one or more faulted devices, and insufficient replicas to continue
The health of the top-level vdev, such as mirror or raidz device, is
potentially impacted by the state of its associated vdevs, or component
devices. A top-level vdev or component device is in one of the following
So from the zpool man page it seems that it is not possible to put a single
device zpool in a degraded state. Is this correct or does the fix in Bugs
6565042 and 6322646 change this behavior.
>Also, just want to ensure everyone is on the same page here. There seems to be
>>some mixed messages in this thread about how sensitive ZFS is to SAN issues.
>Do we all agree that creating a zpool out of one device in a SAN environment
>is >not recommended. One should always constructs a zfs mirror or raidz device
>out >of SAN attached devices, as posted in the ZFS FAQ?
The zpool man page seem to agree with this. Is this correct?
This message posted from opensolaris.org
zfs-discuss mailing list