Since 1999, sar on Linux has used this default directory structure.
/var/log/sa
Currently that structure is used on RedHat Linux and dirivatives.
On Debian and variants (Ubuntu, Mint,...) , sar files are probably found at /var/log/sysstat
Debian: /etc/sysstat/sysstat
RedHat: /etc/sysconfig/systat
Debian: /usr/lib/sysstat/sadc -V
RedHat: /usr/lib64/sa/sadc -V
By default, the files are in /var/log/sysstat.
Use grep ^SA_DIR /etc/sysstat/sysstat if it exists.
If not, then use the default location.
By default, the files are in /var/log/sa.
Use grep ^SA_DIR /etc/sysconfig/systat if it exists.
If not, then use the default location.
On RedHat, the SA_DIR configuration parameter does not seem to be used prior to Linux 8.
There are three different directory structures that may be used (as of 2022-05-10)
Note: it is assumed that Bash is the current shell.
$ grep -h 'HISTORY=' /etc/{sysconfig,sysstat}/sysstat 2>/dev/null | cut -f2 -d= | tr -d \"
90
If the value returned is 28 or less, then the default directory structure will be /var/log/sa.
The sar files (data, not text) are sa??
So the files would be found as ls -l /var/log/sa/sa??
That is assuming of course the default directory is used (check SA_DIR in the sysstat file)
If the value is GT 28, then things begin to look different.
When HISTORY is set to 29 or more, the files will be archived by year and month in separate directories.
Additionaly, archive files may be compressed.
This value is the number of days after which files are compressed:
Note: STDERR is being discarded, as some versions of grep complain about a missing directory. Just ensure the return value is not empty and is valid.
$ grep -h 'COMPRESSAFTER=' /etc/{sysconfig,sysstat}/sysstat 2>/dev/null | cut -f2 -d= | tr -d \"
10
The compression program used is configured in sysstat
Ubuntu 20:
grep -h 'ZIP=' /etc/{sysconfig,sysstat}/sysstat 2>/dev/null | cut -f2 -d= | tr -d \"
xz
Oracle Linux 7:
# grep -h 'ZIP=' /etc/{sysconfig,sysstat}/sysstat 2>/dev/null | cut -f2 -d= | tr -d \"
bzip2
Determining the platform is not always straightforward.
For several years, all major Linux distributions are using the /etc/os-release file.
Oracle Linux 5 does not use it.
Oracle Linux 6+ does use it.
Though we are not overly concerned with Debian/Ubuntu, any recent versions also use it.
See /etc/os-release
And even when os-release IS used, they do not all use the same parameters.
ID_LIKE is s parameter that would easily discern between RedHat (fedora) and Debian or Ubuntu like releases.
But, not everyone uses it. So, perhaps something this will work:
#!/usr/bin/env bash
# returns 'releaseType:version'
getLinuxVariant () {
local variant
local version
local releaseFile
local oldSchool=N
if [[ -r /etc/os-release ]]; then
releaseFile=/etc/os-release
variant=$(grep -E '^ID=' /etc/os-release| tr -d '[ \"]' | cut -f1 -d\. | cut -f2 -d=)
elif [[ -r /etc/oracle-release ]]; then # old oracle - LT version 6
releaseFile=/etc/oracle-release
oldSchool=Y
variant='oracle'
elif [[ -r /etc/redhat-release ]]; then # old redhat - LT version 6
releaseFile=/etc/redhat-release
variant='redhat'
oldSchool=Y
else
echo 'Cannot find a suitable release file to determine Linux variant'
return 1
fi
[[ -r $releaseFile ]] || { echo "failed to get release file in getLinuxVariant"; exit 1; }
# get major version number
if [[ $oldSchool == 'Y' ]]; then
version=$(grep -v '^\s*#' $releaseFile | head -1 | awk '{ print $NF }')
else
#version=$(grep -E '^VERSION=' /etc/os-release| tr -d \" | cut -f1 -d\. | cut -f2 -d=)
# tr stripping quotes and alpha - ubuntu has alpha characters after the version
version=$(grep -E '^VERSION=' /etc/os-release| tr -d ' \"[[:alpha:]()]+' | cut -f1 -d\. | cut -f2 -d=)
fi
[[ -z $version ]] && { echo "failed to get version in getLinuxVariant"; exit 1; }
[[ -z $variant ]] && { echo "failed to get variant in getLinuxVariant"; exit 1; }
# variants
# rhel: redhat
# fedora: redhat
# ol: oracle
# linuxmint: debian
# ubuntu: debian
local releaseType
if [[ $variant == 'rhel' ]]; then releaseType='redhat'
elif [[ $variant == 'fedora' ]]; then releaseType='redhat'
elif [[ $variant == 'ol' ]]; then releaseType='redhat'
elif [[ $variant == 'oracle' ]]; then releaseType='redhat'
elif [[ $variant == 'linuxmint' ]]; then releaseType='debian'
elif [[ $variant == 'ubuntu' ]]; then releaseType='debian'
elif [[ $variant == 'debian' ]]; then releaseType='debian'
else releaseType='unknown'
fi
echo "$releaseType:$version"
return 0
}
declare -A linuxInfo
while IFS=: read linuxType version
do
linuxInfo['release']=$linuxType
linuxInfo['version']=$version
done < <(getLinuxVariant)
echo release: ${linuxInfo[release]}
echo version: ${linuxInfo[version]}