delete rpm packages ignoring dependent error
#rpm -e –nodeps openssl-0.9.7a-33.17
list all files installed by a package
rpm -ql package_name
Category Archives: Memo
LVM
Setup lvm
combine /dev/sdb and /dev/sdc
if there’s partition on /dev/sdb, /dev/sdc, need to clear them first using fdisk
fdisk /dev/sdb -> d (delete partition) ->w
fdisk /dev/sdc
pvcreate /dev/sdb
pvcreate /dev/sdc
vgcreate vgrp /dev/sdb /dev/sdc
vgchange -a y vg
vgdisplay vg|grep ‘Total PE’
lvcreate -i2 -I8 -l 70006 vg -n lv
vgdisplay vg|grep ‘Total PE
‘lvcreate -i2 -I8 -l 70006 vg -n lv
mkfs.ext3 /dev/vg/lv
tune2fs -r 128000 /dev/vg/lv
mount /dev/vg/lv /backup
Remove lvm
#lvremove /dev/vg/lv
#vgremove vg
#fdisk /dev/sdb
#mkfs.ext3 /dev/sdb1
#tune2fs -r 128000 /dev/sdb1
(do same to /dev/sdc)
#mount /dev/sdb1 /www
Logrotate
Some logrotate are not working properly
added “/var/log/xxx/*/errors” into /etc/logrotate.d/xxx
and change to weekly
/usr/local/zeus/web/log/errors /var/log/xxx/*/errors {
weekly
rotate 8
missingok
create 0644 nobody nobody
compress
}
problem in search
problem when search for “V&R”
V%26amp%3BR
%26 -> &
%3B -> ;
%26amp%3B -> &
Solution: change & to encoded code in query sent to html
Add:
$srch_name=eregi_replace(“&”,”%26amp%3B”,$srch_name);
before the following code
if($srch_name !=”){ $req.=”&name=$srch_name”; }
if($srch_site !=”){ $req.=”&site=$srch_site”; }
MySQL processlist
check mysql queries
mysqladmin processlist -v |less
missing ; before statement
To check Javascript error, use Firefox Web Developer Addon
Tool -> Error Console
Got javascript error as “missing ; before statement” although there was no missing “;”
Finally found the reason is that the javascript function used number at the beginning, like
2way_func = function(){ …..}
awk & Sed
Calculate sum of the file size
ls -l access_log.2008-12-20*|gawk ‘{a+=$5;} END {print a;}’
Edit special lines using regular expression
awk ‘/aaa/ ‘ filename
Change file names using sed
##Example: from access_log.2008-12-20.01.gz.1 to access_log.2008-12-20.01.1.gz
for file in `ls access_log.2008-12-20.*`
do
newname=`echo $file|sed ‘s/\(access_log.2008-12-20.[0-9][0-9]\).gz.\([0-9]*\)/\1.\2.gz/’`
size=`ls -l $file|awk ‘{print $5}’`
if [ $size -gt 100 ];then
echo “$file-> $newname”
fi
mv -v $file $newname
done
trim
trim
get rid of space, \n and \r, etc
$login = trim($_POST[‘user_login’]);
Arrays in PHP
To define an Array
$prod = array();
$prod = array(“a”,”b”,”c”);
$prod = array(
“prod1” => array(“id”=>”prod001″,”date” => “111208”, “name”=>”aaa”);
“prod2” => array(“id”=>”prod002″,”date” => “111108”, “name”=>”bbb”);
“prod3 => array(“id”=>”prod003″,”date” => “111008”, “name”=>”ccc”);
);
$data=array();
$data[‘id’] = 1;
$data[‘name’] = ‘John’;
$data[‘id’] = 1;
$data[‘name’] = ‘John’;
To read values out
foreach($SITE as $key1 => $val1){
foreach($sval1 as $key2 => $val2){
if($key2==”id”) echo “ID: $val2[0]\n”;
}
}
foreach($data as $value){
echo $value.”\n”;
}
Push elements into Array
bash — if
#!/bin/bash
if [ -n "$1" ];then
filename = $1;
else
filename = date --date='1 hour ago'" + %Y-%m-%d.%H"`;
fiCompare numbers with -gt -lt -ne -eq
if [ “${size}” -gt 100 ];then
echo $size
fi
echo $size
fi
Compare strings with = !=
if [ “${domain}” = “lalife.net” ];then
echo “correct”
fi
(#if [ “${domain}”=”lalife.net” ];then (##this won’t work without space around “=” or “!=”)
echo “correct”
fi
(#if [ “${domain}”=”lalife.net” ];then (##this won’t work without space around “=” or “!=”)
When using [[ ]]
if [[ ${domain} = “lalife.net” ]];then
echo “correct”
fi
([ ] needs the variable to be inside of “”)
Match
if [[ ${domain} =~ “lalife.net” ]];then
echo “correct”
fi
([ ] doesn’t work with =~)