Quantum 3.5.1 manual Supported

Models: 3.5.1

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General Operating Guidelines and Limitations

 

 

Operating System /

 

Affected Component

Description

 

 

All

In StorNext 3.0, the default buffer cache settings have been modified.

 

Previously, all reads/writes that were 64K or smaller went through the buffer

 

cache while larger I/O requests went direct. In StorNext 3.0, read/writes that

 

are 1MB or smaller go through the buffer cache, while larger I/O requests go

 

direct.

 

The new buffer cache settings may change the I/O behavior of some

 

applications. For example, on managed servers, I/O to and from tape now

 

goes through the buffer cache. To revert to the settings used in previous

 

releases, change the following mount options on StorNext clients:

 

auto_dma_read_length=65537

 

auto_dma_write_length=65537

 

 

 

In StorNext 3.0, obsolete methods of specifying FSS addresses are no longer

 

supported.

 

If the fsroutes configuration file is present, it is ignored and a warning is

 

generated. In addition, the FSM address field for each entry in the fsmlist

 

configuration file (the second column) is no longer supported and is ignored

 

if present. If the priority field (the third column) is specified, then a period (.)

 

must be used to take the place of the second column.

 

The correct way to specify the metadata network for a cluster is through the

 

addresses in the fsnameservers configuration file. If the address of a name

 

server in fsnameservers is on network <x>, then network <x> will be used as a

 

metadata network.

 

 

 

Don't run multiple copies of fsqueue.

 

The fsqueue command checks the request queue and displays status on

 

requests awaiting resources.

 

Care should be taken to execute only one fsqueue process at a time. Invoking

 

multiple simultaneous instances of fsqueue can consume system resources.

 

The fsqueue process may take some time to complete if the file system

 

contains large directories. Invoking fsqueue directly from a cron job

 

frequently can result in multiple copies of fsqueue to be running at the same

 

time. To run fsqueue from a cron job, wrap it in a shell script that checks to

 

see if it is already running.

 

 

StorNext User’s Guide

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Page 369
Image 369
Quantum 3.5.1 manual Supported