Setting Up Internal Disk Storage; Internal Disk Storage Overview; The Console Log And The /Var/Log/Messages File - NEC Express5800/ftServer Administrator's Manual

Setting Up Internal Disk Storage

Setting Up Internal Disk Storage
This section discusses the following topics:
''Internal Disk Storage
''The Console Log and the /var/log/messages
''Configuring Internal
''Managing
''Default Internal Disk Configuration for a Newly Installed
''Checking the Current State of the Internal Disk
''Storage Device

Internal Disk Storage Overview

ftServer systems support up to six internal Serial Advanced Technology Attachment
SAS (SATA) disks, three in each CPU-I/O enclosure.
You can use RAID 1 to mirror the disks in one enclosure with the corresponding disks
in the other enclosure for fault tolerance. (You should not mirror disks in the same
internal storage enclosure.) RAID 1 directs I/O flow to the appropriate disks in the two
CPU-I/O enclosures. When a CPU-I/O enclosure (or a disk in it) is pulled, the RAID-1
mirrors are broken, the other CPU-I/O enclosure becomes simplex, and its disk status
LED becomes amber. (Pulling the CRU would cause all disk LEDs in the remaining
CRU to go amber. Pulling one disk would cause only its partner's LED to go amber.)
An amber LED indicates that the device is no longer safe to pull. The Opstate Manager
(OSM) administratively removes the missing mirrors from their RAID 1 arrays.
When the CPU-I/O enclosure is re-inserted, the SAS (SATA) driver spins up the disk(s),
and the OSM administratively adds the mirrors back into their RAID arrays. The other
CPU-I/O enclosure remains simplex until all mirror synchronization completes. (The
RAID-1 fast resync feature can greatly reduce resync time.)
SAS (SATA), RAID, DM-multipath, and OSM plug-ins are independent modules that
interact with each other.

The Console Log and the /var/log/messages File

The system console displays messages from the internal storage subsystem. This
includes messages when disks are inserted and removed and when disk errors occur.
The console messages are also in the system log (/var/log/messages). Tailing the
messages file while configuring disks is very helpful.
# tail -f /var/log/messages
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