Top 50 CISCO ACI interview questions & answers

Cisco ACI is a part of Software Defined Network (SDN) product portfolio from Cisco . Cisco ACI is an emerging technology on DC build up and disruptive technology for traditional networking .This Question and Answers guide will help you to understand Cisco ACI from basics to advanced level and give confidence to tackling the interviews with positive result . You can download PDF of 50 Q&A from here by contributing small amount of money for our effort.

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1.What is Cisco ACI.?
Cisco ACI, the industry-leading software-defined networking solution, facilitates application agility and data center automation with two important concepts from SDN solution, overlays and centralized control. ACI is a is a well defined architecture with centralised automation and policy-driven application profiles. ACI uses a centralised controller called the Application Policy Infrastructure Controller (APIC),It is the controller that creates application policies for the data center infrastructure.

2. What are the three components of ACI architecture .?
Application Network Profile (ANP)– a collection of end-point groups (EPG), their connections, and the policies that define those connections
Application Policy Infrastructure Controller (APIC)– a centralized software controller that manages downstream switches and act as management plane.
ACI fabric : This is connection of Spine and Leaf switches. In the ACI world Spine and Leaf are the Cisco Nexus 9000 Series Switches (N9k) , and they are act as Control and the Data plane of the ACI. It is running re written version of NX-OS in ACI mode.


3. Describe about ACI Fabric connection terminology.?
• You should use One or more spine switches to be connected to each Leaf, Models supported are Cisco Nexus 9336PQ, 9504, 9508, or 9516 switches
• You should use One or more leaf switches to be connected to End Points and APIC cluster , Models supported are Cisco Nexus 93128TX, 9332PQ, 9372PX, 9372PX-E, 9372TX, 9396PX, or 9396TX etc switches
• Spin switches can be connected to leaf switches but not each other.
• Leaf switches can be connected only to spine switches and endpoint devices including APIC devices , so this means APIC will be connected only to Leaf switches
• ACI Switches are not running spanning tree.
• Minimum 3 APIC controller should require in ACI fabric
• Max APIC can be used are 5
• Max Spine switches can be used are 6
• Max Leaf switches can be used are 200

4. What is the use of Application Policy Infrastructure Controller (APIC) on ACI Fabric.?
This is the network controller is responsible for provisioning policies to physical and virtual devices that belong to an ACI fabric. Minimum a cluster of three controllers is used. Following are the main APIC features.

  • Application and topology monitoring and troubleshooting
  • APIC shows Physical and logical topology (who is connected to whome)
  • Third-party integration (Layer 4 through Layer 7 [L4-L7] services & VMware vCenter/ vShield)
  • Image management (spine and leaf)
  • Cisco ACI inventory and configuration
  • Implementation on a distributed framework across a cluster of appliances
  • Health scores for critical managed objects (tenants, application profiles, switches, etc.)
  • Fault, event, and performance management
  • Cisco Application Virtual Switch (AVS), which can be used as a virtual leaf switch

5. How Cisco ACI differs from other SDN controllers.?
Open SDN architecture separates control plane and data plane . Control plane resides on the central controller and data plane resides on switches. If the switches lost connection to controller, it won’t function for new connections and applying traffic policies. In CIsco ACI architecture , the APIC is not control plane, rather switches still hold control plane and data plane and can function properly if the controller down.

6. What are the different object model implementation in ACI.?
Within the ACI object model, there are essentially three stages of implementation of the model, the Logical Model, the Resolved Model, and the Concrete Model.
Logical Model: The logical model is the interface for the system. Administrators are interacting with the logical model through the API, CLI, or GUI. This is a Policy layer which include endpoint configuration on the controller .Changes to the logical model are then pushed down to the concrete model, which becomes the hardware and software configuration.
Resolved Model : The Resolved Model is the abstract model expression that the APIC resolves from the logical model. This is essentially the elemental configuration components that would be delivered to the physical infrastructure when the policy must be executed (such as when an endpoint connects to a leaf)
Concrete Model : The Concrete Model is the actual in-state configuration delivered to each individual fabric member based on the resolved model and the Endpoints attached to the fabric.This is include actual configuration of device and resides on fabric (spines and leafes )

7.What is Policy layer and Concrete Layer in ACI model.?
Concrete layer is the ACI fabric and policy layer is controllers

8.What you mean by Tenant .?
Basically a Tenant (fvTenant) is logical container for application policies to isolate switching and routing function. A tenant represents a unit of isolation from a policy perspective, but it does not represent a private network. Tenants can represent a customer in a service provider setting, an organisation or domain in an enterprise setting, or just a convenient grouping of policies.
Four types of Tenant available

  1. User
  2. Common
  3. Management
  4. Infra

9 . Difference between management tenant and infrastructure tenant.?
Management Tenant : Used for infrastructure discovery and also used for all communication/integration with virtual machine controllers. It has separate Out Of Band (OOB) address space for APIC to Fabric communication, it is using to connect all fabric management interfaces
Infrastructure Tenant : It governs operation of fabric resources like allocating VXLAN overlays and allows fabric administrator to deploy selective shared services to tenants

10.What you mean by Context/VRF on ACI .?
The top level network construct within an ACI tenant is the VRF or Context . It is called as tenant network and available as ‘private network’ in the ACI GUI .Following are the important point about VRF’s
• A VRF defines Layer 3 address domain
• One or more bridge domain can associated with VRF
• All of the endpoints within the Layer 3 domain (VRF) must have unique IP addresses because it is possible to forward packets directly between these devices if the policy allows it.
• A tenant can contain multiple VRFs How ARP handled by ACI.?

Below are some of the additional questions available on PDF

  • How ARP and broadcast handled by ACI.?
  • Why and when you require contract in ACI Fabric.?
  • How to perform unicast routing on ACI.?
  • In Fabric, which switch will act as default gateway for pertucler subnet.?
  • How Cisco ACI differentiate Layer 2 traffic and Layer 3 traffic.?
  • How VLAN working in Cisco ACI.?
  • How can you configure trunk and access port on ACI.?
  • What is micro segmentation and how to configure.?
  • How to configure inter-VRF and Inter-tenant communication.?
  • How can you integrate Cisco ACI with VmWare.?
  • Explain about ACI fabric discovery process .?
  • Explain about traffic flow lookup on ACI fabric.?

Interested to know about the detailed answers of above questions along with other exclusive commonly asked 30 interview questions.? You can download PDF copy of 50 interview Q&A from here by contributing small perks to support our efforts. Please send email to ‘[email protected]‘ for PayPal payment option.


Hope you have enjoyed reading. Kindly share your feedback/suggestions in the comments section. For Q&A posts on other topics, please click here.

Ref:
https://www.sdxcentral.com/data-center/definitions/what-is-cisco-aci/

https://www.cisco.com/c/en_in/solutions/data-center-virtualization/application-centric-infrastructure/index.html

Network Automation using Python – Part VII – SSL certificate status validation and alert configuration

Python SSL Certificate Checker 

Continuing our Networking Automation using Python blog series, here is the Part 7.

In this part we are explaining python script which will check the expiry date of a SSL certificate from a list of IP address and send an e-mail automatically if the certificate expiry date is nearing. The IP addresses can be of your load balancer VIP or Server IP address or any device IP address. You can use same script to check SSL certificate for any port number like 443,587,993,995,465 etc.

Basic Requirements Read more

  1. Python 3.6
  2. server_ip.txt , a text file which contains all device IP address
  3. A email account on www.outlook.com . You can use any other mail account by editing SMTP server detail on the script. Please let us know if you want customised script which will sent mail from your corporate mail account or Microsoft Outlook.

Please read part 1 and part 2 to get started with python and how to run your first program.

This script have two files

  1. server_ip.txt -> this file store all the device IP address
  2. sslcheck.py -> This is the python script

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How to run :

Step 1. Download the sslcheck and server_ip to the same folder

Step 2. Change the sslcheck.txt to sslcheck.py

Step 3. Open server_ip.txt and save with all your device IP address with port number whose SSL certificate need to be check.

Step 4. Open command prompt “CMD” and navigate to the folder where you have saved script and ‘server_ip.txt’

Step 5. Run script by typing “python sslcheck.py”  on command prompt

Step 6.It will ask for threshold date, from mail id , to mail id and credentials. Please provide the same

Step 7. Script will go though each device SSL certificate and sent mail if anything going to expire within given number of days.

 

Script Details

import ssl
from datetime import datetime
import pytz
import OpenSSL
import socket
import getpass
from datetime import timedelta
import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

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print(“Program to check SSL certificate validity \n”)
##opening file
ipfile=open(‘server_ip.txt’)
cur_date = datetime.utcnow()
mailbody=””
expcount=0

##getting details
expday=input(“Please provide threshold expiry date :”)
from_mail=input(“Your mail id : “)
passwd=getpass.getpass(“password : “)
to_mail=input(“Target mail id : “)
##checking certificate validity. for loop to go through each IP in server_ip.txt file

for ip in ipfile:
try:
host = ip.strip().split(“:”)[0]
port = ip.strip().split(“:”)[1]
print(“\nChecking certifcate for server “,host)
ctx = OpenSSL.SSL.Context(ssl.PROTOCOL_TLSv1)
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, int(port)))
cnx = OpenSSL.SSL.Connection(ctx, s)
cnx.set_connect_state()
cnx.do_handshake()
cert=cnx.get_peer_certificate()
s.close()
server_name = cert.get_subject().commonName
print (server_name)

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##checking expiry date
edate=cert.get_notAfter()
edate=edate.decode()

##converting in to system time format
exp_date = datetime.strptime(edate,’%Y%m%d%H%M%SZ’)
days_to_expire = int((exp_date – cur_date).days)
print(“day to expire”,days_to_expire)
##preparing mail body
if days_to_expire < int(expday) :
expcount=expcount+1
mailbody=mailbody+”\n Server name =”+server_name+”, Days to expire:”+str(days_to_expire)

except:
print (“error on connection to Server,”,host)
print (mailbody)

#sending mail if any certificate going to expire within threshold days
if expcount >= 1 :
try:
print(“\nCertifcate alert for “+str(expcount)+” Servers,Sending mails”)

body=”Following certificate going to expire, please take action \n”+mailbody
s = smtplib.SMTP(host=’smtp-mail.outlook.com’, port=587) # change here if you want to use other smtp server
s.starttls()
s.login(from_mail,passwd)

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msg = MIMEMultipart() # create a message
msg[‘From’]=from_mail
msg[‘To’]=to_mail
msg[‘Subject’]=”Certificate Expire alert”
# add in the message body
msg.attach(MIMEText(str(body),’plain’))

# send the message via the server set up earlier.
s.send_message(msg)
print(“Mail sent”)
s.close()
except:
print (“Sending mail failed”)
else :
print(“All certificate are below the threshold date”)

print (‘\nCert check completed’)

 

Sample Output 

Below images are sample script and a sample e-mail alert.

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Sample e-mail alert

Hope this post helped you. You can read more posts on Network automation using Python here. Please use the comments section for any queries/suggestions .

Reference :

https://www.python.org/

http://www.tutorialspoint.com/python/ 

Network Automation using Python – Part VI – Automatic backup of multiple switches

Python Backup Script

 

Continuing our Networking Automation using Python blog series, here is the Part 6.

Here we are explaining a simple script to take the backup of multiple Cisco switches/routers quickly. You can schedule the script using crone or job scheduler so it will automatically take daily backup without your intervention. The script will take the output of ‘sh run’ and save to the file. The file name would be  device IP address + today’s date .

Please read part 1 and part 2 to get started with python and to run your first program. Please read part 4 for detailed steps on how to take an SSH session of a switch.

Read more

The script have two files

  1. ipfile.txt -> this file store all the device IP address
  2. autobackup.py -> This is the python script

How to run :

Step 1. Download the autobackup and iplist to the same folder

Step 2. Change the autobackup.txt to autobackup-cisco.py

Step 3. Open iplist.txt and save with all your device IP address which need to be backed up.

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Step 4. Open command prompt “CMD” and navigate to the folder where you have saved script and ‘iplist.txt’

Step 5. Run script by typing “python autobackup-cisco.py”  on command prompt

Step 6. You can see the backup of device on same folder with the filename device IP address+ date

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Sample screenshot below.

Hope this post helped you.

You can read more posts on Network automation using Python here. Please use the comments section for any queries/suggestions .

Reference :

https://www.tutorialspoint.com/python

https://www.python.org/

Network Automation using Python – Part V – running a set of commands on Cisco switches

Python Script to run set of commands

Continuing our Networking Automation using Python blog series, here is the Part 5.

This post details about an all-in-one script which will helps you to execute series of commands in multiple switches. This script can be utilized by peoples who does not have much idea in scripting. We have made this task in three file to simplify the operation so that you don’t have to change the script every time .

Please read part 1 and part 2 for details about installing python and running your first program. Please read part 4 if you want to know how to take SSH of a switch.

Read more

File details :
  1. Configuration file-> This file include all the configuration commands need to be executed on remote switches. The name of the file is ‘configfile.txt’
  2. IP File -> This file contains IP address of all the devices, file named ‘ipfile.txt’
  3. Script file -> This files contains python script to execute commands specified on configuration file on all devices. (filename here is ‘configcommand.py’)

For example , if i need to update ACL 101 which is  applied to outside interface of all routers, follow the below steps.

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Step 1. Open your ‘configfile.txt’ and add following commands

config terminal
access-list 101 permit ip 10.1.1.0 0.0.0.255 172.16.1.0 0.0.0.255
end
write

Step 2. Open ‘iplist.txt’ and add all your router IP address

Step 3. Open command prompt and give following command to execute

cmd->python configcommand.py

 

Working : 

The script will login to the first device whose IP address mentioned in ‘ipfile.txt’ and execute all the commands given in ‘configfile.txt’ file. Once it is done, the script will login to the next IP address and execute all the commands. The process will continue until the last IP address on the ‘ipfile.txt’ fetch and execute.

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You can use the same script to execute any kind of command like SNMP modification, interface configuration etc. All you just want to edit ‘configfile.txt’ and no need to edit the script file.

 

Complete Script – Download

Click below links to  download script (to SSH to a device and run multiple commands) and other file  Please change the file extension from .txt to .py for executing directly.

Script- configcommand

Configfile –configfile

iplist.txt –iplist

Also, keeping a copy here in this post below.

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from netmiko import ConnectHandler
import getpass,sys,time

device = {
‘device_type’: ‘cisco_ios’,
‘ip’: ‘192.168.43.10’,
‘username’: ‘username’,
‘password’: ‘password’,
‘secret’:’password’
}
ipfile=open(“iplist.txt”)
print (“Script for SSH to device, Please enter your credential”)
device[‘username’]=input(“User name “)
device[‘password’]=getpass.getpass()
device[‘secret’]=input(“Enter enable password: “)
configfile=open(“configfile.txt”)
configset=configfile.read()
configfile.close()

for line in ipfile:

device[‘ip’]=line.strip(“\n”)
print(“\n\nConnecting Device “,line)
net_connect = ConnectHandler(**device)
net_connect.enable()
time.sleep(2)
print (“Passing configuration set “)
net_connect.send_config_set(configset)
print (“Device Conigured “)

ipfile.close()

Hope you enjoyed reading. You can read more posts on Network automation using Python here. Please use the comments section for any queries/suggestions .

Reference :

https://www.python.org/

https://www.tutorialspoint.com/python

Network Automation using Python – Part IV – SSH to Cisco Device

SSH Cisco Device

Continuing our Networking Automation using Python blog series, here is the Part 4.

We had explained the ways to take a Telnet session to the Switches in our previous posts. Now here we are explaining the steps to SSH to Cisco switch using Python script and to configure IP on vlan interface. IP configuration is an example here, once you have SSH’ed to the switch, you can perform any other configuration as per your requirement, by just modifying the script a bit. Please read part 1 and part 2 to get an idea about how to install python and run your first program.

We are using netmiko module for taking SSH session of device.

What is Netmiko ?

Read more

Netmiko is open-source Python library that simplifies SSH management to network devices. This is a common and easy to use library as netmiko supporting multi vendor devices.You can read more about netmiko from here . Following are the some of the vendor devices supported by Netmiko .

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Arista vEOS
Cisco ASA
Cisco IOS
Cisco IOS-XR
Cisco NX-OS
Cisco SG300
HP Comware7

Cisco IOS-XE
HP ProCurve
Juniper Junos
Linux

How to install Netmiko

Netmiko package not available by default. You should have netmiko library installed on your machine .Following are the steps to download and install netmiko in Python 3.6

Step 1. Working internet connection and Python 3.6 installed on machine

Step 2. On command prompt, type following command, this will automatically fetch netmiko from internet and install on your machine

“python -m pip install netmiko”

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Following are the steps to start with netmiko on your script

Import netmiko to your Script

Use the following command to import netmiko package to your script

from netmiko import ConnectHandler

Create Device template 

We have to create device template using python dictionary data type.

device = {
‘device_type’: ‘cisco_ios’,
‘ip’: ‘10.10.10.10’,
‘username’: ‘admin’,
‘password’: ‘Beginnersforum’,
‘port’ : 22,
‘secret’: ‘enablepassword’# optional, replace with your enable password ”
}

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where,

device ->This is name of template, you can give any name like cisco_2960,juniper_sw etc

‘device_type’ -> Here we are specifying the type of device we are taking ssh,

secret -> Here we are giving the enable password

Port and secret are optional here and the default value for port is 22.

Establish an SSH connection to the device

We are estabishing SSH connection to device by passing the above defined template

ssh_connect = ConnectHandler (**cisco_switch)

Run Show command 

Here the ‘show ip int brief” command will execute on remote device and output will store to ‘result” variable. We can print “result” to see the output on window

result = net_connect.send_command(show ip int brief) print(result)

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Sample output :

Interface IP-Address OK? Method Status Protocol
FastEthernet0 unassigned YES unset down down
FastEthernet1 unassigned YES unset down down
FastEthernet2 10.10.10.10 YES manual up up
Vlan1 unassigned YES unset down down

Complete Script – Download

You can download script (to SSH to a device and add IP address to vlan 10) from here. Please change the file extension from .txt to .py for executing directly.

Also, keeping a copy here in this post below.

 

from netmiko import ConnectHandler
import getpass
import sys

#create device template

device = {
‘device_type’: ‘cisco_ios’,
‘ip’: ‘192.168.43.10’,
‘username’: ‘username’,
‘password’: ‘password’,
‘secret’:’password’
}

#Getting the user credential

print (“Script for SSH to device, Please enter your credential”)
device[‘username’]=input(“User name “)
device[‘password’]=getpass.getpass()
device[‘secret’]=input(“Enter enable password”)

#Establishing SSH connection
ssh_connect = ConnectHandler(**device)

#changing to enable mode
ssh_connect.enable()
ssh_connect.send_command(‘config t’)
ssh_connect.send_command(‘int vlan 10’)
ssh_connect.send_command(‘ip add 10.10.10.1 255.255.255.0)
ssh_connect.send_command(‘end’)
ssh_connect.send_command(‘write’)
ssh_connect.disconnect()

Hope you enjoyed reading. You can read more posts on Network automation using Python here. Please use the comments section for any queries/suggestions .

Reference :

https://www.tutorialspoint.com/python

https://www.python.org/

Network Automation using Python – Part II – Telnet to a Switch and IP configuration

This is the 2nd post from my Networking Automation using Python blog series.

As part of network automation, the first thing is accessing (Telnet -ing) a switch. Here is a simple program explaining step by step way to access Cisco switch using telnet and to configure IP address on Vlan interface – all using Python.

Please check out our first post Network Automation using Python – Part I for getting started with Python. We have explained the basics of Python and the installation procedure in the previous post.

“telnetlib” module

Read more

“telnetlib” is the name of module which is supporting to take the telnet of device. This will be automatically installed as part of your python installation

->Import telnet library

The first step is to import telnet library to our script , use the following command

“import telnetlib”

->Connecting a Host

To connect a device using telnetlib, use following command.

tn=telnetlib.Telnet(HOST)

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Where HOST is the variable which is having the IP address of device and “tn” is the           variable name which is creating virtual telnet link with your device. It could be any name as you wish ( like telnet or tnet) .You should use same name for the rest of the             operation on the device.

-> Writing  command to to Host

tn.write(“config t”)

The write() function using to deliver command to device. The above example will write       “config t”  command on the device telnet prompt.

-> Reading output from host

output=tn.read_all()

read_all() function will read the output of command from device and store in to the variable output

That concludes the basics for initiating a telnet session to the switch.

Following are the step by step guidelines to access the switch and then configure the IP on the switch. The steps explained below is based on 2.6 version for easy understanding. I have attached version 3.6 and 2.6 script also as there are changes in the script. The main difference in 3.6 as we need to convert all values in to ASCII before sending to device.

Step 1. Importing the required modules

import telnetlib

import getpass

import time

“getpass” is the module to read the password without printing on screen

“time” will be using to control the flow of program by pausing script certain duration

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Step 2. Initialise the Host Variable

The “Host” variable holding the IP address of Device . We can assign the IP address as follows. Please understa

HOST=”192.168.43.10″

Step 3. Read the user name and password

user = raw_input(“Enter your telnet username: “)
password = getpass.getpass()

raw_input() is an in built function used to read data giving by user and assigning to a variable. Here it will display “Enter your telnet username” on the screen and read the username provided by user and assign to variable called user. After executing those lines, we will have username on “user” variable and password on “password” variable.

Step 4. Connect to device and supply username and password

tn = telnetlib.Telnet(HOST)

tn.read_until(“Username: “)

tn.write(user + “\n”)

if password:

tn.read_until(“Password: “)

tn.write(password + “\n”)

tn = telnetlib.Telnet(Host)    // This command will initiate a telnet session to the given IP address on background .

tn.read_until(b”Username: “)    // This will be used to read output from device until it is asking for ‘Username’

tn.write(user + “\n”)   // This will supply the username to the telnet console followed by enter key. “\n” using to provide enter key.

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Step 5. Configure the device

In this step, we will be delivering configuration command to device one by one

tn.write(“enable\n”)    // changing to enable mode
tn.write(“cisco\n”)      // providing enable password
tn.write(“conf t\n”)     //moving to configuration mode
tn.write(“int vlan 10 \n”)   // changing to vlan 10 interface
tn.write(“ip address 1.1.1.1 255.255.255.255\n”)  // Assigning the IP address
tn.write(“end\n”)    //ending the configuration
tn.write(“exit\n”)

We have delivered all commands using write() function. You can use same write function to deliver the command as per your requirement. Save and Execute the script using RUN . Please refer part 1 if you don’d know how to write and execute script.

Script download

You can download the script for version 2.6, here

You can download the script for version 3.6, here

 

So, that’s it. Hope this helped you. You can read more posts on Network automation using Python here. Please use the comments section for your queries/comments.

Reference :

http://www.python.org/

www.tutorialspoint.com/python

Network Automation using Python – Part I – Python basics

Network Automation using Python

We are starting with series of posts which will help you to automate your networking tasks using Python. This is a step by step guide which will show how to install Python and start your first program. You do not require any programming skill to start with automation. Please keep watching  on upcoming posts to understand better.

What is Python

Python is a general-purpose interpreted, interactive, object-oriented, and high-level programming language. It was created by Guido van Rossum during 1985- 1990. Like Perl, Python source code is also available under the GNU General Public License (GPL). This tutorial gives understanding how to install python one Windows machine and make it ready for Network Automation programming. Here in this post I will be covering only essential parts to start with Python so that we can continue with the network automation things in the coming posts. Please follow https://www.tutorialspoint.com/python/index.htm for more on basic/advanced python training.

Read more

Download Python

Download python from following link. You can either download 2.7 version or latest 3.6 version.Here we are showing 3.6 version since this is the latest and our all automation scripts are based on 3.6 version.

https://www.python.org/downloads/

Install Python.

Double click on the downloaded exe file and proceed with next until it gets installed.Leave all values default.

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Accessing Python.

Once it is installed, it will be available in  program list.

Click on Start-All Programs-Python 3.6  and click on IDLE .IDLE is the name of IDE for Python scripting .

Writing your first Program:

Once you have clicked IDLE, you will be available with following window.

To start with new program , click file -> New file. This will open new window where you can start coding.Here we will write a program to print Hello World . You can directly start coding from first line on wards as  python does not require any ‘main’ or ‘initialization’ statements for simple programs.

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Save the program

Click file and Save to save the program . The program will be saving with .py extension

Run the program.

Python does not require any compilation before running program as python is an interpreter program. To run the program , Select Run and click on Run Module

The result of the program will available on the first window. (Shell window)

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Accessing program from command line.

You can use following method to run the script which is created earlier or given by someone else. To run the program from command line, open CMD and navigate to the folder where your script has been saved .Type python and after that script file name on CMD. This will run the script and provide the out put on command prompt.

Hope you got the idea how to install Python and run your first program. Please click here for more posts from this series. Please use the comments section in case if you have any queries.

Reference:

https://www.tutorialspoint.com/python

https://www.python.org/

Cisco MDS SAN switch Zoning via CLI

Here let’s discuss the steps to complete the zoning of a new server in Cisco MDS FC switch. In our previous post we had discussed the initialization procedure for a new MDS switch – may be helpful for you. The process of zoning will have 3 components, namely aliases, zones and zoneset (or zone configuration).

If you have a Brocade switch, you may refer to this post which explains zoning in a Brocade switch via CLI.

An alias is a name assigned to the WWN numbers which makes it easy to use/remember. WWN numbers Read more

– identity for a device, will have numbers separated by colon (:), for e.g, 10:ab:cd:ef:12:34:56:78 – are harder to be remembered.

A zone will be containing multiple objects which defines a communication path. In a zoning enabled switch, any two WWNs or port which are not having a common zone (which are not part of a single zone together) will not be able to communicate each other. We will create a Zone and will add the objects (WWNs, aliases or ports) to it.

A zoneset or a zone configuration is a collection of a set of zones in a switch/fabric. It makes easy to manage the zones. We will define an active configuration in switch/fabric and will add the zones, which need to be active, to this configuration.
Now let’s discuss the commands.

 

 

First we will create an alias for the new server HBA and the storage port to which it need to communicate.

#conifg -t

BForum_SAN01(config)# fcalias name BForum_HBA1 vsan 20        # This will create an alias with name BForum_HBA1

BForum_SAN01(config-alias)# member pwwn 10:xx:xx:xx:xx:xx:xx:01    # Adds the WWN to this alias

BForum_SAN01(config-alias)#exit

BForum_SAN01(config)# fcalias name VNX_SPA3 vsan 20

BForum_SAN01(config-alias)# member pwwn 50:xx:xx:xx:xx:xx:xx:01

BForum_SAN01(config-alias)#exit

Now we have the aliases ready. We can now create a zone for these two objects and add them. We will create a zone named ‘BForum_HBA1_VNX_SPA3’ which will be containing the host HBA (BForum_HBA1) and the storage port (VNX_SPA3).

BForum_SAN01(config)# zone name BForum_HBA1_VNX_SPA3 vsan 20

BForum_SAN01(config-zone)# member fcalias BForum_HBA1

BForum_SAN01(config-zone)# member fcalias VNX_SPA3

BForum_SAN01(config-zone)# exit

Zone too is ready now. Assuming we don’t have an existing configuration, we will be creating a zone config here. If you are already having a zoneset, you can use the zoneset name here in the below command.

 

 

BForum_SAN01(config)#zoneset name BForum_SAN01_Config VSAN 20

BForum_SAN01(config-zoneset)# member BForum_HBA1_VNX_SPA3

BForum_SAN01(config-zoneset)# exit

Now we have the zoneset created and zones added to it. We are good to activate the new zoneset.

BForum_SAN01(config)# zoneset activate name BForum_SAN01_Config VSAN 20

To verify the active zoneset, you may run the command show active zoneset

In case if you have to deactivate the zoneset, you may run the command,

BForum_SAN01(config)# no zoneset activate name BForum_SAN01_Config VSAN 20

We can save the running config to start-up config by running copy run start command. Now we have the zoning completed for one of the HBA of the new server. We will have to do the zoning for both the HBAs and should use multiple storage ports for redundancy.

You may click here for SAN switch related posts.

Hope this post was helpful for you. More, in coming posts, your thoughts in comments below… 🙂

Initializing a Cisco MDS FC switch

Trouble in initializing brand new Cisco MDS FC switch ? This post may help you. This post here discusses the procedure to initialize a new FC switch.

MDS_9124

You have to connect the Console cable with Read more

the serial (COM) port on your laptop/desktop. You may use any terminal emulation utility such as Putty, Hyper Terminal etc.. and should use the default settings for serial connection (9600 baud,8 data bits,1 stop bit,No parity). Now you are all set to receive get the serial console.

 

Now you can connect the power and switch the switch ON. Once the switch is powered ON and booted up, you will asked to set the password for administrator. You should be setting a strong password otherwise the entered one will be rejected.

Once this is done, you will be prompted whether or not to continue with entering the configuration data. You can proceed with yes once you have the necessary information.

 

 

Press Enter at anytime to skip a dialog. Use ctrl-c at anytime
to skip the remaining dialogs.

Would you like to enter the basic configuration dialog (yes/no): yes

Create another login account (yes/no) [n]:

Configure read-only SNMP community string (yes/no) [n]:

Configure read-write SNMP community string (yes/no) [n]:

Enter the switch name : B-Forum-SW01

Continue with Out-of-band (mgmt0) management configuration? (yes/no) [y]:

Mgmt0 IPv4 address : 12x.23x.234.123

Mgmt0 IPv4 netmask : 255.255.255.0

Configure the default gateway? (yes/no) [y]:

IPv4 address of the default gateway : 12x.23x.234.1

Configure advanced IP options? (yes/no) [n]:

Enable the ssh service? (yes/no) [y]:

===== Output shortened =====

 

 

The switch will be showing all the parameters going  to be set on the switch. If you need to edit any of them, you may enter yes for the query to edit. If you are OK with the values, you can go for the default , no.You can save the configuration by entering yes to the next query.

Would you like to edit the configuration? (yes/no) [n]: no

Use this configuration and save it? (yes/no) [y]: yes

The switch will reboot and the new configuration will take affect. Yes, we are done..

If you wish to reset these values later, you may try the command setup. You will be receiving the same questionnaire as you did for the first time initialization.

You may click here for SAN switch related posts.

Hope this post was helpful for you. Comments are always welcome…