AIX系统日志学习笔记之三

一、系统硬件诊断工具

AIX还给我门提供了diag命令来判断问题，并且分析问题。

#diag

比如：

# diag -d sysplanar0 -v –e

http://www.kuqin.com/aixcmds/aixcmds2/diag.htm

 

二、查看系统日志

在AIX中可以使用alog命令来查看系统日志。

# man alog

alog Command

Purpose

       Creates and maintains fixed-size logfiles created from standard input.

Syntax

To Show theContents of a Log File

       alog -f LogFile [ -o ]

To Log Data to aSpecified Log File

       alog -f LogFile | [ [ -q ] [ -s Size ] ]

To Display theVerbosity Value of a Specified Log Type

       alog -t LogType -V

...skipping...

alog Command

Purpose

       Creates and maintains fixed-size logfiles created from standard input.

Syntax

To Show the Contents of a Log File

       alog -f LogFile[ -o ]

To Log Data to a Specified Log File

       alog -f LogFile| [ [ -q ] [ -s Size ] ]

To Display the Verbosity Value of a Specified Log Type

       alog -t LogType-V

To Change the Attributes of a Specified Log Type

       alog -C -tLogType [ -f LogFile ] [ -s Size ] [ -w Verbosity ]

To Display the Current Attributes of a Specified Log Type

       alog -L [ -tLogType ]

To Display the Usage of the alog Command

       alog -H

Description

       The alog command reads standard input,writes to standard output, and

       copies the output into a fixed-sizefile. This file is treated as a

       circular log. If the file is full, newentries are written over the

       oldest existing entries.

       The alog command works with log filesthat are specified on the command

       line or with logs that are defined inthe alog configuration database.

       Logs that are defined in the alogconfiguration database are identified

       by LogType. The File, Size, andVerbosity attributes for each defined

       LogType are stored in the alogconfiguration database with the LogType.

       You can add a new LogType to the alogconfiguration database using the

       odmadd command. You can change theattributes of LogType defined in the

       alog configuration database using thealog command.

Flags

       -C

            Changes the attributes for aspecified LogType. Use the -C flag

            with the -f, -s, and -w flags tochange the File, Size, and

            Verbosity attributes for the specifiedLogType. The -t LogType

            flag is required.

            Note: Using the -C flag with -sSizeonly changes the size value in

            ODM and does not change the size ofthe actual log file.

            If the -C flag is used, the alogcommand does not copy standard

            input to standard output or to alog file.

            When the -C flag is used to modifythe attributes for the console

            log type, the console log file isalso modified and the console

            device driver is updated to use thenew values. This is a

            deviation from the normal operationof alog -C and is done to

            accommodate special formatting inthe console log file.

            Note: You must have root userauthority to change alog attributes.

       -f LogFile

            Specifies the name of a log file.If the specified log file does

            not exist, one is created. If thealog command is unable to write

            to a log file, it writes to/dev/null. Use the -f LogFile flag

            with the -C and -t flags to changethe File attribute for a

            LogType defined in the alogconfiguration database.

       -H

            Displays the usage of the alogcommand.

       -L

            Lists the log types currentlydefined in the alog configuration

            database. If you use the -L flagwith the -t LogType flag, the

            attributes for a specified LogTypeare listed. The current values

            of the File, Size, and Verbosityattributes are listed as colon

            separated values:

           <File>:<Size>:<Verbosity>

            If the -L flag is used, the alogcommand does not copy standard

            input to standard output or toFile.

       -o

            Lists the contents of the log file.Writes the contents of the log

            file to standard output insequential order.

       -q

            Copies standard input to a log filebut does not write to standard

            output.

       -s Size

            Specifies the size limit of the logfile in bytes. The space for

            the log file is reserved when it iscreated. If you create a new

            log file and do not specify theSize attribute, the minimum size,

            4096 bytes, is used. If the logfile already exists, its size will

            be changed. The size you specify isrounded upward to the next

            integral multiple of 4096 bytes.The maximum size for a log file

            is 2 GB. If the specified size isgreater than 2 GB, only 2 GB is

            considered. If you decrease thesize of the log file, the oldest

            entries in the log are deleted ifthey do not fit within the new

            size limit. You must have writepermission for the log file to

            change its size.

            Use the -s Size flag with the -Cand the -t flags to change the

            Size attribute for LogType definedin the alog configuration

            database. Only the size value inODM is changed. The size of the

            actual log file remains the same.The new Size attribute value is

            used the next time a log file iscreated.

       -t LogType

            Identifies a log defined in thealog configuration database. The

            alog command gets the log's filename and size from the alog

            configuration database. If LogFiledoes not exist, one is created.

            If the alog command cannot get theinformation for the specified

            LogType from the alog configurationdatabase or if the alog

            command is unable to write toLogFile, it writes to /dev/null.

            If you specify LogType and LogFileusing the -f flag, LogFile is

            used and LogType is ignored.

       -V

            Writes the current value of theVerbosity attribute for LogType

            that is defined in the alogconfiguration database to standard

            output. If you do not specifyLogType, or the LogType you specify

            is not defined, nothing is written tostandard output.

            The value output using the alogcommand with the -t LogType and

            the -V flags can be used by acommand that is piping its output to

            the alog command to control theverbosity of the data it writes to

            the pipe.

       -w Verbosity

            Changes the Verbosity attribute forLogType defined in the alog

            configuration database when usedwith the -C and the -t flags.

            The Verbosity attribute can have avalue from 0 to 9. If the value

            is 0, no information is copied toLogFile by the alog command. All

            of the information is still writtento standard output. If the

            value is not 0, all of theinformation piped to the alog command's

            standard input is copied to LogFileand to standard output.

 

Examples

       1   To record the current date and time in a log file named

            sample.log, enter:

            #date | alog -f /tmp/sample.log

       2   To list the contents of /tmp/sample.log log file, enter:

            #alog -f /tmp/sample.log -o

       3   To change the size of the log file named /tmp/sample.log to 8192

            bytes, enter:

            #echo "resizing log file"| alog -f /tmp/sample.log -s 8192

       4   To add a new log type sample to the alog configuration database,

            create the alog.add file in thefollowing format:

            SWservAt:

                attribute="alog_type"

                deflt="sample"

                value="sample"

            SWservAt:

               attribute="sample_logname"

               deflt="/tmp/sample.log"

               value="/tmp/sample.log"

            SWservAt:

                attribute="sample_logsize"

                deflt="4096"

                value="4096"

            SWservAt:

               attribute="sample_logverb"

                deflt="1"

                value="1"

            After creating the alog.add file,enter:

            #odmadd alog.add

            This adds the alog.add file to theSWservAt database.

       5   To change the name of the log file for the log type sample to

            /var/sample.log in the alogconfiguration database, enter:

            #alog -C -t sample -f /var/sample.log

       6   To change the size of the boot log to 8192 bytes and reflect the

            new size in ODM, enter:

            alog -C -t boot -s 8192

            echo "Changed log size" |alog -t boot -s 8192

Files

       /etc/objrepos/SWservAt

            Software Service Aids AttributesObject Class

RelatedInformation

       The odmadd command.

       How to Add Objects to an Object Class inAIX Version 6.1 General

       Programming Concepts: Writing andDebugging Programs.

 

常用的命令

查看日志类型

# alog -L

boot

bosinst

nim

console

cfg

mdmplog

lvmt

lvmcfg

dumpsymp

 

日志文件的大小可以通过以下命令来修改

#alog –t boot –s 8192

 

显示系统启动的信息

# alog -o -t boot | more

 

显示console信息

#alog –o –t console

 

显示lvm的信息

# alog -t lvmcfg –o