август 2017

CONFIGURE DHCP SERVER ON A CISCO ROUTER

Posted on август 22, 2017 | by rutera | Leave a Comment

Конфигуриране на DHCP сървър на Cisco рутер.

Топология

Започваме с конфигурацията на рутера

R1# configure terminal
R1(config)# service dhcp

1 2	R1# configure terminal R1(config)# service dhcp

сега създаваме DHCP pool

R1(config)# ip dhcp pool NET-POOL
R1(dhcp-config)# network 192.168.1.0 255.255.255.0

1 2	R1(config)# ip dhcp pool NET-POOL R1(dhcp-config)# network 192.168.1.0 255.255.255.0

продължаваме с конфига

R1(dhcp-config)# default-router 192.168.1.1
R1(dhcp-config)# dns-server 192.168.1.5 195.170.0.1
R1(dhcp-config)# domain-name Firewall.cx
R1(dhcp-config)# lease 9

R1(dhcp-config)# default-router 192.168.1.1

R1(dhcp-config)# dns-server 192.168.1.5 195.170.0.1

R1(dhcp-config)# domain-name Firewall.cx

R1(dhcp-config)# lease 9

мрежата която ще раздава ип-та

R1(config)# ip dhcp excluded-address 192.168.1.1 192.168.1.5
R1(config)# ip dhcp excluded-address 192.168.1.10

1 2	R1(config)# ip dhcp excluded-address 192.168.1.1 192.168.1.5 R1(config)# ip dhcp excluded-address 192.168.1.10

резултат

R1# show ip dhcp binding 
Bindings from all pools not associated with VRF:
IP address Client-ID/ Lease expiration Type
Hardware address/
User name
192.168.1.6 0100.1e7a.c409 Jan 19 2009 03:06 PM Automatic
192.168.1.7 0100.1e7a.c3c1 Jan 19 2009 09:00 PM Automatic
192.168.1.8 0100.1ebe.923b Jan 19 2009 02:25 PM Automatic
192.168.1.9 0100.1b53.5ccc Jan 19 2009 02:03 PM Automatic
192.168.1.11 0100.1e7a.261d Jan 19 2009 07:52 PM Automatic
R1#

R1# show ip dhcp binding

Bindings from all pools not associated with VRF:

IP address Client-ID/ Lease expiration Type

Hardware address/

User name

192.168.1.6 0100.1e7a.c409 Jan 19 2009 03:06 PM Automatic

192.168.1.7 0100.1e7a.c3c1 Jan 19 2009 09:00 PM Automatic

192.168.1.8 0100.1ebe.923b Jan 19 2009 02:25 PM Automatic

192.168.1.9 0100.1b53.5ccc Jan 19 2009 02:03 PM Automatic

192.168.1.11 0100.1e7a.261d Jan 19 2009 07:52 PM Automatic

R1#

реинджа в който ще се раздават адреси е 192.168.1.5-10

Увеличаване броя на max_connections в MySQL

Posted on август 10, 2017 | by rutera | Leave a Comment

Проверяваме броя като се логнем с root в mysql

mysql> SHOW VARIABLES LIKE "max_connections";

+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 150   |
+-----------------+-------+
1 row in set (0.00 sec)

mysql> SHOW VARIABLES LIKE "max_connections";

+-----------------+-------+

| Variable_name | Value |

+-----------------+-------+

| max_connections | 150 |

+-----------------+-------+

1 row in set (0.00 sec)

стандарнто са 150.

Сега може да ги увеличим по следния начин

mysql> SET GLOBAL max_connections = 250;

1	mysql> SET GLOBAL max_connections = 250;

след това отиваме в конфигурацията на mysql – my.cnf

За Debian базираните системи обикновенно се намира в /etc/mysql/my.cnf

За CentOS и RHEL базираните системи обикновенно се намира в /etc/my.cnf

и добавяме следния ред

max_connections = 250

1	max_connections = 250

след което рестартираме mysql.

Резултата е

 SHOW VARIABLES LIKE "max_connections";
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 250   |
+-----------------+-------+
1 row in set (0.00 sec)

SHOW VARIABLES LIKE "max_connections";

+-----------------+-------+

| Variable_name | Value |

+-----------------+-------+

| max_connections | 250 |

+-----------------+-------+

1 row in set (0.00 sec)

Скриване версията на Apache

Posted on август 10, 2017 | by rutera | Leave a Comment

С цел по-голяма защита можем да скрием версията на Apache и по този начин няма да се показва в хедъра.

За целта отиваме в конфигурацията на apache

/usr/local/apache/conf/httpd.conf

1	/usr/local/apache/conf/httpd.conf

и добавяме следните два реда

ServerTokens Prod
ServerSignature Off

1 2	ServerTokens Prod ServerSignature Off

след което рестартираме apache

service httpd restart

1	service httpd restart

Преди да направим промените

curl -I http://localhost

HTTP/1.1 200 OK
Date: Thu, 10 Aug 2017 06:56:30 GMT
Server: Apache/2.4.27 (Unix) OpenSSL/1.0.1e-fips
Last-Modified: Sun, 30 Jul 2017 17:12:47 GMT
ETag: "13cd-5558c05f3b7c6"
Accept-Ranges: bytes
Content-Length: 5069
Content-Type: text/html

HTTP/1.1 200 OK

Date: Thu, 10 Aug 2017 06:56:30 GMT

Server: Apache/2.4.27 (Unix) OpenSSL/1.0.1e-fips

Last-Modified: Sun, 30 Jul 2017 17:12:47 GMT

ETag: "13cd-5558c05f3b7c6"

Accept-Ranges: bytes

Content-Length: 5069

Content-Type: text/html

след като направихме промените

HTTP/1.1 200 OK
Date: Thu, 10 Aug 2017 06:57:44 GMT
Server: Apache
Last-Modified: Sun, 30 Jul 2017 17:12:47 GMT
ETag: "13cd-5558c05f3b7c6"
Accept-Ranges: bytes
Content-Length: 5069
Content-Type: text/html

HTTP/1.1 200 OK

Date: Thu, 10 Aug 2017 06:57:44 GMT

Server: Apache

Last-Modified: Sun, 30 Jul 2017 17:12:47 GMT

ETag: "13cd-5558c05f3b7c6"

Accept-Ranges: bytes

Content-Length: 5069

Content-Type: text/html

How to Install Ruby 2.4.0 on CentOS/RHEL with RVM

Posted on август 9, 2017 | by rutera | Leave a Comment

Подготвяне на инсталацията

# yum install gcc-c++ patch readline readline-devel zlib zlib-devel
# yum install libyaml-devel libffi-devel openssl-devel make
# yum install bzip2 autoconf automake libtool bison iconv-devel sqlite-devel

# yum install gcc-c++ patch readline readline-devel zlib zlib-devel

# yum install libyaml-devel libffi-devel openssl-devel make

# yum install bzip2 autoconf automake libtool bison iconv-devel sqlite-devel

Инсталиране на RVM(Ruby Version Manager)

# curl -sSL https://rvm.io/mpapis.asc | gpg --import -
# curl -L get.rvm.io | bash -s stable

1 2	# curl -sSL https://rvm.io/mpapis.asc \| gpg --import - # curl -L get.rvm.io \| bash -s stable

Проверка на зависимости

# rvm requirements run

Checking requirements for centos.
Requirements installation successful.

# rvm requirements run

Checking requirements for centos.

Requirements installation successful.

Инсталиране на Ruby 2.4

# rvm install 2.4.0

1	# rvm install 2.4.0

Searching for binary rubies, this might take some time.
Found remote file https://rvm_io.global.ssl.fastly.net/binaries/ubuntu/16.04/x86_64/ruby-2.4.0.tar.bz2
Checking requirements for ubuntu.
Requirements installation successful.
ruby-2.4.0 - #configure
ruby-2.4.0 - #download
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 16.4M  100 16.4M    0     0   724k      0  0:00:23  0:00:23 --:--:--  790k
No checksum for downloaded archive, recording checksum in user configuration.
ruby-2.4.0 - #validate archive
ruby-2.4.0 - #extract
ruby-2.4.0 - #validate binary
ruby-2.4.0 - #setup
ruby-2.4.0 - #gemset created /usr/local/rvm/gems/ruby-2.4.0@global
ruby-2.4.0 - #importing gemset /usr/local/rvm/gemsets/global.gems..............................
ruby-2.4.0 - #generating global wrappers........
ruby-2.4.0 - #gemset created /usr/local/rvm/gems/ruby-2.4.0
ruby-2.4.0 - #importing gemsetfile /usr/local/rvm/gemsets/default.gems evaluated to empty gem list
ruby-2.4.0 - #generating default wrappers........

Searching for binary rubies, this might take some time.

Found remote file https://rvm_io.global.ssl.fastly.net/binaries/ubuntu/16.04/x86_64/ruby-2.4.0.tar.bz2

Checking requirements for ubuntu.

Requirements installation successful.

ruby-2.4.0 - #configure

ruby-2.4.0 - #download

% Total % Received % Xferd Average Speed Time Time Time Current

Dload Upload Total Spent Left Speed

100 16.4M 100 16.4M 0 0 724k 0 0:00:23 0:00:23 --:--:-- 790k

No checksum for downloaded archive, recording checksum in user configuration.

ruby-2.4.0 - #validate archive

ruby-2.4.0 - #extract

ruby-2.4.0 - #validate binary

ruby-2.4.0 - #setup

ruby-2.4.0 - #gemset created /usr/local/rvm/gems/ruby-2.4.0@global

ruby-2.4.0 - #importing gemset /usr/local/rvm/gemsets/global.gems..............................

ruby-2.4.0 - #generating global wrappers........

ruby-2.4.0 - #gemset created /usr/local/rvm/gems/ruby-2.4.0

ruby-2.4.0 - #importing gemsetfile /usr/local/rvm/gemsets/default.gems evaluated to empty gem list

ruby-2.4.0 - #generating default wrappers........

Задаване на дефаултна версия на Ruby

# rvm list

rvm rubies

 * ruby-2.3.0 [ x86_64 ]
   ruby-2.3.3 [ x86_64 ]
=> ruby-2.4.0 [ x86_64 ]

# => - current
# =* - current && default
#  * - default


-----
# rvm use 2.4.0 --default

Using /usr/local/rvm/gems/ruby-2.4.0

# rvm list

rvm rubies

* ruby-2.3.0 [ x86_64 ]

ruby-2.3.3 [ x86_64 ]

=> ruby-2.4.0 [ x86_64 ]

# => - current

# =* - current && default

# * - default

-----

# rvm use 2.4.0 --default

Using /usr/local/rvm/gems/ruby-2.4.0

Провереряваме версията

# ruby --version

1	# ruby --version