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Python Script for Getting Effective Zone Configuration from a Brocade SAN Switch

This python script connects given san switch through ssh then gets the effective zone information then parses the output and print semicolon separated list in the form of:
zone_name;world_wide_number;switch_name
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Python Script for Generating Random Passwords

This Python script is practical for generating random passwords.

A password contains:
7 lowercase alphabetic characters.
2 uppercase alphabetic characters.
2 numeric characters.
1 special character. (special char will be one of these: ! + % ? * - _ )

3 Node (Master Slave Slave) Redis Cluster with Sentinel

It is possible to make your Redis cluster Fault Tolerant and Highly Available by building a replica set and then monitor these nodes using sentinel for automatic failover.
I am going to give an example setup to explain it. The structure is built with three nodes running one as a master and two as slaves.
Master Node: (Centos 7.2) 192.168.1.11 Slave1 Node: (Centos 7.2) 192.168.1.12 Slave2 Node: (Centos 7.2) 192.168.1.13
Edit System settings on each node: /etc/sysctl.conf
Disable transparent hugepage (transparent_hugepage=never) on each node: /etc/default/grub
Apply grub config and reboot each node:
Master Node: /etc/redis/6379.conf
Slave1 Node: /etc/redis/6379.conf
Slave2 Node: /etc/redis/6379.conf
Master Node: /etc/redis/sentinel.conf
Slave1 Node: /etc/redis/sentinel.conf
Slave2 Node: /etc/redis/sentinel.conf
Each Node: /etc/systemd/system/multi-user.target.wants/redis-server.service
Each Node: /etc/systemd/system/multi-user.target.wants/redis-sentinel.service
After creating service files reload sy…

Common HTTP Load Balancing Methods

Estimating utilization of the application servers may not be always possible. In many companies, while average cpu utilization of any server is changing between %20 and %30, they may become hardly respond to incoming requests at peak times. When an unexpected over-utilization occurs, the first method that comes to mind is provisioning new instances (of course your company is using a virtualization or cloud architecture) to the application server pool.
Sometimes it may not be the solution for over-utilization. As the number of app servers increases it becomes important that the requests are distributed equally across these servers. Becoming some of the servers unresponsive may have a devastating effect on the environment.

Traditionally, load balancers are used to distribute incoming traffic across multiple app instances. Load balancing provides some benefits like scaling the application farm, supporting heavy network traffic, detecting unhealthy app instances and automatically removin…