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'GNU/Linux'

CentOS’da NTP kurulumu

16 July 2008 | Kategori: Documents, GNU/Linux | Yorum (0)

CentOS Linux sunucunuzun saat sürekli olarak bir ileri, iki geri şeklinde gidiyor, müşterilerden sürekli “sunucunun saati yanlış” diye geri dönüşler geliyor ve siz hala “date” ile uğraşıyorsanız, boşuna uğraşıyorsunuz.
Kurun sunucunuza bir NTP servisi, saat/tarih işleriyle o ilgilensin.

“NTP nedir” derseniz, hemen sözlük’ten bir alıntı yapayım; network time protocol un kisaltilmisi. bilgisayarlar arasinda network yada internet uzerinden zamanlarin senkronizasyonunu saglar. linuxta rdate komutu ile bir tane timeserver adresi girerseniz bilgisayariniz o serverin saati ile senkronize olur.

Öncelikle kurulu değilse, YUM paket yöneticisi ile ntp paketinin kurulumu yapalım.
# yum install ntp

Kurulum sonrasında servisi başlatalım.
# chkconfig ntpd on

Sunucu saatinizi public bir NTP sunucusu olan time.windows.com’dan senkronize edelim.
# ntpdate time.windows.com

NTP’yi başlatalım…
# /etc/init.d/ntpd start

Web üzerinden network izleme

24 June 2008 | Kategori: Documents, GNU/Linux | Yorum (0)

Uzun bir süredir geliştirilmekte olduğunu gördüğüm ancak her nedense yeni keşfetttiğim bir yeme de yanında yat bir alet; ntop.
Kendisinin işi konsoldan showtraf veya iptraf programlarıyla yaptığınızın hemen hemen tıpkısının aynısı. (Belki keşfedemediğim daha birkaç ekstra özelliği de olabilir ntop’ın.)
Kurulum şeysinden bahsetmeye gerek bile yok.. Centos 4.5′de rpm -Uhv ftp://rpmfind.net/linux/dag/redhat/el4/en/i386/dag/RPMS/ntop-3.2-2.el4.rf.i386.rpm ile, Debian 3.1′de ise apt-get install ntop ile işimizi halledip, konsola ntop yazmamız yeterli.
İlk seferinde sizden bir admin parolası girmenizi isteyecektir…
Ardından hooop: http://IPADRESI:3000

Ramback geldi, hoş geldi

26 May 2008 | Kategori: GNU/Linux | Yorum (0)

Daha bir arada göremediğim boyutlardaki RAM’ler için hazırlanmış Ramback, kernelimizin yeni ve güzide patchlerinden birisi.

Eğlenceli ve farklı bir eleman ilanı

17 May 2008 | Kategori: Funny, GNU/Linux | Yorum (0)

From: alperyilmaz@crypttech.com Alper YILMAZ
To: linux-ik@liste.linux.org.tr
Date: Thu, 15 May 2008 16:16:28 +0300
Subject: [Linux-ik] 3L3M4N Ih7iY4cI - 4ciL — Eleman Ihtiyaci - Acil

Bilgi güvenliği projelerinde yer alacak, tecrübeli (linux) ve yetiştirilmek
üzere elaman alınacaktır.

Anahtar Kelimeler:
Linux
Security
Crypto
Hack
TakeDown http://www.imdb.com/title/tt0159784/
Swordfish http://www.imdb.com/title/tt0244244/

Not: Erkek adaylarda en az 2 sene askerlik tecili istenmektedir.

Sirket: Crypttech (Kriptek) www.crypttech.com
Yer: Istanbul

Ilgilenen arkadaslar cv lerini ik@crypttech.com yada
alperyilmaz@crypttech.com adresine göndersinler.

İki ayrı bilgisayarda klavye/mouse paylaşımı; Synergy2

22 April 2008 | Kategori: Documents, GNU/Linux | Yorum (0)

Tuhaf bir başlık oldu, kabul.
İşin aslı şu; masanızda birden fazla bilgisayar var. Misal benim gibi, sol tarafınızda Ubuntu kurulu dizüstü bilgisayarınız, sağ tarafınızda Windows XP kurulu şirketin masaüstü bilgisayarı.
Her bilgisayar için ayrı ayrı klavye ve mouse kullanmak yerine bir tane server seçip, ikinci (veya üçüncü/dördüncü ~) bilgisayarları client olarak ayarlayabilirsiniz. Bu sayede server olarak seçtiğiniz bilgisayarın klavye ve mouse’unu kullanarak diğer bilgisayarların yönetimini gerçekleştirebilirsiniz.
Ubuntu/Windows üzerinde yalnızca ekran koruyucularını ve kopyala/yapıştır özelliklerini kullanabiliyorken, Windows/Windows ortamında pencereleri bilgisayarlar arasında paylaşabiliyorsunuz.
Bazı eksikleri ve limitleri olsa da bu haliyle bile son derece kullanılabilir, kurulumu son derece kolay bir çalışma olmuş.
TCP/IP üzerinden bu işlemi yapan dahiane yazılımını ismi; Synergy2.
Windows, RPM ve kaynak kod dosyalarını kendi sitesinden, Ubuntu paketlerini şuradan bulabilirsiniz.
Örnek olması açısında Ubuntu üzerindeki yapılandırma dosyam şu şekilde;

GNU nano 2.0.6 File: /home/arda/.synergy.conf

section: screens
blueberry:
blackberry:
end
section: links
blackberry:
right = blueberry
blueberry:
left = blackberry

end

rm -rf /

27 March 2008 | Kategori: Funny, GNU/Linux | Yorum (0)

Hep yapmak istemişimdir.. Demin bir sanal sunucu açarak, denedim.

ardatest:~# cat /etc/debian_version
3.1
ardatest:~# rm -rf -v /
removed `//bin/tempfile’
removed `//bin/gzip’
removed `//bin/sh’
removed `//bin/mv’
removed `//bin/touch’
removed `//bin/rbash’
removed `//bin/login”
removed `//bin/ls’
removed `//bin/cp’
removed `//bin/df’
removed `//bin/rmdir’p’
removed `//bin/mount’
(….)
removed directory: `//sbin’
rm: cannot remove `//sys/class/tty/ptmx/dev’: Operation not permitted
rm: cannot remove `//sys/class/tty/ptmx/uevent’: Operation not permitted
rm: `//sys/class/tty/ptmx/subsystem’ changed dev/ino: Operation not permitted
ardatest:~#
ardatest:~# rm -rf -v /
-bash: /bin/rm: No such file or directory

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Array ( [Variable_name] => back_log [Value] => 50 )

Array ( [Variable_name] => basedir [Value] => /sh_sys/mysql-4.1.22/ )

Array ( [Variable_name] => binlog_cache_size [Value] => 32768 )

Array ( [Variable_name] => bulk_insert_buffer_size [Value] => 8388608 )

Array ( [Variable_name] => character_set_client [Value] => latin5 )

Array ( [Variable_name] => character_set_connection [Value] => latin5 )

Array ( [Variable_name] => character_set_database [Value] => latin5 )

Array ( [Variable_name] => character_set_results [Value] => latin5 )

Array ( [Variable_name] => character_set_server [Value] => latin5 )

Array ( [Variable_name] => character_set_system [Value] => utf8 )

Array ( [Variable_name] => character_sets_dir [Value] => /sh_sys/mysql-4.1.22/share/mysql/charsets/ )

Array ( [Variable_name] => collation_connection [Value] => latin5_turkish_ci )

Array ( [Variable_name] => collation_database [Value] => latin5_turkish_ci )

Array ( [Variable_name] => collation_server [Value] => latin5_turkish_ci )

Array ( [Variable_name] => concurrent_insert [Value] => ON )

Array ( [Variable_name] => connect_timeout [Value] => 10 )

Array ( [Variable_name] => datadir [Value] => /sh_sys/mysql-4.1.22/var/ )

Array ( [Variable_name] => date_format [Value] => %Y-%m-%d )

Array ( [Variable_name] => datetime_format [Value] => %Y-%m-%d %H:%i:%s )

Array ( [Variable_name] => default_week_format [Value] => 0 )

Array ( [Variable_name] => delay_key_write [Value] => ON )

Array ( [Variable_name] => delayed_insert_limit [Value] => 100 )

Array ( [Variable_name] => delayed_insert_timeout [Value] => 300 )

Array ( [Variable_name] => delayed_queue_size [Value] => 1000 )

Array ( [Variable_name] => expire_logs_days [Value] => 0 )

Array ( [Variable_name] => flush [Value] => OFF )

Array ( [Variable_name] => flush_time [Value] => 0 )

Array ( [Variable_name] => ft_boolean_syntax [Value] => + -><()~*:""&| )

Array ( [Variable_name] => ft_max_word_len [Value] => 84 )

Array ( [Variable_name] => ft_min_word_len [Value] => 4 )

Array ( [Variable_name] => ft_query_expansion_limit [Value] => 20 )

Array ( [Variable_name] => ft_stopword_file [Value] => (built-in) )

Array ( [Variable_name] => group_concat_max_len [Value] => 1024 )

Array ( [Variable_name] => have_archive [Value] => NO )

Array ( [Variable_name] => have_bdb [Value] => NO )

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Array ( [Variable_name] => have_compress [Value] => YES )

Array ( [Variable_name] => have_crypt [Value] => YES )

Array ( [Variable_name] => have_csv [Value] => NO )

Array ( [Variable_name] => have_example_engine [Value] => NO )

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Array ( [Variable_name] => have_isam [Value] => NO )

Array ( [Variable_name] => have_merge_engine [Value] => YES )

Array ( [Variable_name] => have_ndbcluster [Value] => NO )

Array ( [Variable_name] => have_openssl [Value] => NO )

Array ( [Variable_name] => have_query_cache [Value] => YES )

Array ( [Variable_name] => have_raid [Value] => NO )

Array ( [Variable_name] => have_rtree_keys [Value] => YES )

Array ( [Variable_name] => have_symlink [Value] => YES )

Array ( [Variable_name] => init_connect [Value] => )

Array ( [Variable_name] => init_file [Value] => )

Array ( [Variable_name] => init_slave [Value] => )

Array ( [Variable_name] => innodb_additional_mem_pool_size [Value] => 1048576 )

Array ( [Variable_name] => innodb_autoextend_increment [Value] => 8 )

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Array ( [Variable_name] => innodb_buffer_pool_size [Value] => 8388608 )

Array ( [Variable_name] => innodb_data_file_path [Value] => ibdata1:10M:autoextend )

Array ( [Variable_name] => innodb_data_home_dir [Value] => )

Array ( [Variable_name] => innodb_fast_shutdown [Value] => ON )

Array ( [Variable_name] => innodb_file_io_threads [Value] => 4 )

Array ( [Variable_name] => innodb_file_per_table [Value] => OFF )

Array ( [Variable_name] => innodb_flush_log_at_trx_commit [Value] => 1 )

Array ( [Variable_name] => innodb_flush_method [Value] => )

Array ( [Variable_name] => innodb_force_recovery [Value] => 0 )

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Array ( [Variable_name] => innodb_locks_unsafe_for_binlog [Value] => OFF )

Array ( [Variable_name] => innodb_log_arch_dir [Value] => )

Array ( [Variable_name] => innodb_log_archive [Value] => OFF )

Array ( [Variable_name] => innodb_log_buffer_size [Value] => 1048576 )

Array ( [Variable_name] => innodb_log_file_size [Value] => 5242880 )

Array ( [Variable_name] => innodb_log_files_in_group [Value] => 2 )

Array ( [Variable_name] => innodb_log_group_home_dir [Value] => ./ )

Array ( [Variable_name] => innodb_max_dirty_pages_pct [Value] => 90 )

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Array ( [Variable_name] => innodb_mirrored_log_groups [Value] => 1 )

Array ( [Variable_name] => innodb_open_files [Value] => 300 )

Array ( [Variable_name] => innodb_table_locks [Value] => ON )

Array ( [Variable_name] => innodb_thread_concurrency [Value] => 8 )

Array ( [Variable_name] => interactive_timeout [Value] => 600 )

Array ( [Variable_name] => join_buffer_size [Value] => 8384512 )

Array ( [Variable_name] => key_buffer_size [Value] => 268435456 )

Array ( [Variable_name] => key_cache_age_threshold [Value] => 300 )

Array ( [Variable_name] => key_cache_block_size [Value] => 1024 )

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Array ( [Variable_name] => log [Value] => OFF )

Array ( [Variable_name] => log_bin [Value] => OFF )

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Array ( [Variable_name] => log_slave_updates [Value] => OFF )

Array ( [Variable_name] => log_slow_queries [Value] => ON )

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Array ( [Variable_name] => long_query_time [Value] => 1 )

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Array ( [Variable_name] => lower_case_file_system [Value] => OFF )

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Array ( [Variable_name] => max_allowed_packet [Value] => 1047552 )

Array ( [Variable_name] => max_binlog_cache_size [Value] => 4294967295 )

Array ( [Variable_name] => max_binlog_size [Value] => 1073741824 )

Array ( [Variable_name] => max_connect_errors [Value] => 10 )

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Array ( [Variable_name] => max_insert_delayed_threads [Value] => 20 )

Array ( [Variable_name] => max_join_size [Value] => 4294967295 )

Array ( [Variable_name] => max_length_for_sort_data [Value] => 1024 )

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Array ( [Variable_name] => open_files_limit [Value] => 32768 )

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Array ( [Variable_name] => port [Value] => 4306 )

Array ( [Variable_name] => preload_buffer_size [Value] => 32768 )

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Array ( [Variable_name] => query_cache_limit [Value] => 1048576 )

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Array ( [Variable_name] => query_cache_size [Value] => 0 )

Array ( [Variable_name] => query_cache_type [Value] => ON )

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Array ( [Variable_name] => query_prealloc_size [Value] => 8192 )

Array ( [Variable_name] => range_alloc_block_size [Value] => 2048 )

Array ( [Variable_name] => read_buffer_size [Value] => 1044480 )

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Array ( [Variable_name] => read_rnd_buffer_size [Value] => 2093056 )

Array ( [Variable_name] => relay_log_purge [Value] => ON )

Array ( [Variable_name] => relay_log_space_limit [Value] => 0 )

Array ( [Variable_name] => rpl_recovery_rank [Value] => 0 )

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Array ( [Variable_name] => skip_networking [Value] => OFF )

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Array ( [Variable_name] => slave_transaction_retries [Value] => 0 )

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Array ( [Variable_name] => sort_buffer_size [Value] => 2097144 )

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