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memcached set max memory used

admin — Wed, 02 May 2012 13:39:43 +0000

memcached -d -m 2048 -u root

- this console command set max used memory of memcached is 2048 MB

memcached -h
memcached 1.4.5
-p TCP port number to listen on (default: 11211)
-U UDP port number to listen on (default: 11211, 0 is off)
-s UNIX socket path to listen on (disables network support)
-a access mask for UNIX socket, in octal (default: 0700)
-l interface to listen on (default: INADDR_ANY, all addresses)
-d run as a daemon
-r maximize core file limit
-u assume identity of (only when run as root)
-m max memory to use for items in megabytes (default: 64 MB)
-M return error on memory exhausted (rather than removing items)
-c max simultaneous connections (default: 1024)
-k lock down all paged memory. Note that there is a
limit on how much memory you may lock. Trying to
allocate more than that would fail, so be sure you
set the limit correctly for the user you started
the daemon with (not for -u user;
under sh this is done with ‘ulimit -S -l NUM_KB’).
-v verbose (print errors/warnings while in event loop)
-vv very verbose (also print client commands/reponses)
-vvv extremely verbose (also print internal state transitions)
-h print this help and exit
-i print memcached and libevent license
-P save PID in , only used with -d option
-f chunk size growth factor (default: 1.25)
-n minimum space allocated for key+value+flags (default: 48)
-L Try to use large memory pages (if available). Increasing
the memory page size could reduce the number of TLB misses
and improve the performance. In order to get large pages
from the OS, memcached will allocate the total item-cache
in one large chunk.
-D Use as the delimiter between key prefixes and IDs.
This is used for per-prefix stats reporting. The default is
“:” (colon). If this option is specified, stats collection
is turned on automatically; if not, then it may be turned on
by sending the “stats detail on” command to the server.
-t number of threads to use (default: 4)
-R Maximum number of requests per event, limits the number of
requests process for a given connection to prevent
starvation (default: 20)
-C Disable use of CAS
-b Set the backlog queue limit (default: 1024)
-B Binding protocol – one of ascii, binary, or auto (default)
-I Override the size of each slab page. Adjusts max item size
(default: 1mb, min: 1k, max: 128m)

anti ddos script

admin — Tue, 01 May 2012 12:01:14 +0000

http://habrahabr.ru/post/84172/

#!/bin/bash 
# chmod 755 anti_ddos.sh
# ./anti_ddos.sh
 
 
#find
cat /var/log/nginx/error.log | grep "limiting connections by zone" | grep "request: \"GET / HTTP/1.1"| awk '{print $12}'| awk -F"," '{print $1}'| sort | uniq -c | sort -nr > /tmp/botnet.blacklist
 
#/tmp/botnet.blacklist
# очищаем скрипт бана
cat /dev/null > /tmp/iptables_ban.sh
 
# создаем DROP правила для 50 самых агрессивных ботов
awk '{print "iptables -A INPUT -p tcp --dport 80 -s " $2 " -j DROP" }' /tmp/botnet.blacklist | head -n 50 >> /tmp/iptables_ban.sh
 
# загружаем blacklist
bash /tmp/iptables_ban.sh
 
# делаем ротацию лога
cat /dev/null > /var/log/nginx/error.log
[ ! -f /var/run/nginx.pid ] || kill -USR1 `cat /var/run/nginx.pid`
 
 
*/5 * * * * /root/script/ban.sh
 
В результате iptables будет пополнятся новыми ботами.

php call function on exit

admin — Fri, 27 Apr 2012 15:10:32 +0000

you need to use http://php.net/manual/en/function.register-shutdown-function.php

Free alternative of teleport pro is httrack

admin — Mon, 09 Apr 2012 11:54:07 +0000

http://www.httrack.com/page/2/en/index.html

It allows you to download a World Wide Web site from the Internet to a local directory, building recursively all directories, getting HTML, images, and other files from the server to your computer. HTTrack arranges the original site’s relative link-structure. Simply open a page of the “mirrored” website in your browser, and you can browse the site from link to link, as if you were viewing it online. HTTrack can also update an existing mirrored site, and resume interrupted downloads. HTTrack is fully configurable, and has an integrated help system.

301 javascript redirect for google from old website domain to new domain

admin — Mon, 02 Apr 2012 09:00:38 +0000

gz unzip gz file from php

admin — Wed, 21 Dec 2011 08:03:17 +0000

php example code


function uncompress($srcName, $dstName) {
    $sfp = gzopen($srcName, "rb");
    $fp = fopen($dstName, "w");
 
    while ($string = gzread($sfp, 4096)) {
        fwrite($fp, $string, strlen($string));
    }
    gzclose($sfp);
    fclose($fp);
}
uncompress('codhacks.sql.gz','codhacks.sql');echo 1;exit;

Analyse Logging commands for debian linux

admin — Fri, 23 Sep 2011 18:27:22 +0000

http://stackoverflow.com/questions/473998/tool-or-language-to-count-occurrances-of-errors-in-a-log-file

http://www.thinkplexx.com/learn/article/webperf/baslog/statwithbashandawk

awk ‘{print $1}’ access.log|sort -u
awk ‘{print $2}’ access.log|sort -u
awk ‘{print $3}’ access.log|sort -u

The awk filters out all IP addresses, the sort then removes duplicates.

To find out all accesses to a URL, I do

grep URL access.log

Apache2ctl configtest debian apache

admin — Sun, 04 Sep 2011 17:31:39 +0000

How to test debian config in apache ? in debian ?
mnake
/usr/sbin/apache2ctl configtest

find files of some user (linux)

admin — Fri, 12 Aug 2011 07:57:53 +0000

find / -user forumcv

Starting PostgreSQL 8.3 database server: mainThe PostgreSQL server failed to start.

admin — Thu, 21 Jul 2011 15:41:14 +0000

Starting PostgreSQL 8.3 database server: mainThe PostgreSQL server failed to start. Please check the log output: 2011-07-21 18:34:55 EEST FATAL: unsafe permissions on private key file “server.key” 2011-07-21 18:34:55 EEST DETAIL: File must be owned by the database user or root, must have no write permission for “group”, and must have no permissions for “other”. failed!
failed!

HOw to fix ?
easy

Work Around:

1) Enter the relevant directory (use> locate server.key)
2) Back up old server.key link.
3) Copy ssl-cert-snakeoil.key to server.key
4-5) Change its owner & group to postgres
6) Ensure the permissions are 700 or 740 (as requested by error message)

Recipe for my w/ postgresql-8.3 (beware of typos):

cd /var/lib/postgresql/8.3/main/
mv server.key server.key-0
cp /etc/ssl/private/ssl-cert-snakeoil.key server.key
chown postgres server.key
chgrp postgres server.key
chmod 740 server.key
/etc/init.d/postgresql-8.3 start