How to RUN GNS3 with lower Memory and CPU consumption on a Laptop

New GNS3 Setup With Lower CPU Load and Lower Memory Consumption ..Try It !!!

Some Things I've learnt about GNS3

I am in no way an expert on GNS3, just a trainee   below are a few things i have learnt lately. I thought it might be a good idea to produce something like this. If everyone replied to it and added a few tips of their own it could be turned into a CLN GNS3 tips and tricks document.

GNS3 Web Sites
http://www.gns3.net GNS3’s primary Web site
http://wiki.gns3.net GNS3’s Wiki site
http://www.ipflow.utc.fr/index.php/Cisco_7200_Simulator Dynamips – the actual emulator

http://www.ipflow.utc.fr/blog/ Dynamips blog
http://dyna-gen.sourceforge.net/ Dynagen
http://www.ipflow.utc.fr/bts/ Dynamips/Dynagen bug tracking
http://7200emu.hacki.at Hacki’s forum
===

1. GNS3 has less chance of crashing if the bin files are unzipped.

2. Currently images for 2600 routers must be uncompressed to work with Dynamips.

3. To dramatically reduce the load on your processor, right click on the router and choose idle, after a few moments it will give you a list to choose from.
Choose the one with a * against it, if you don't see a * in the choice run it again.

4. If you don't need any special routers then use the same type on the whole lab, this will use far less processing power and memory.

5. To print out the diagram of your network click file then export, you can export all or just what is visible.

6. To move your router/routers/links etc click the left mouse button and draw around what you want to move, you can then move everything that is inside that shape.

7. I find that if you move around the interface identities they eventually go back to their original position. I don't move them anymore as it looks a bit
messy when that happens.

8. You can't use GNS3 for the SWITCH studies, GNS3 only has basic switch capabilities.

9. You can create computers and run ping's/telnet with VPC, the document attached shows you how, its very simple to follow. I did find that it takes a few times for it to accept being a cloud, once you click ok just open it back up and check it.

10. I personally find that it is best to connect your links between routers when they are switched off, sometimes i find it fails otherwise.

11. You can create a router to act like a pc, this is shown below but it is also in the document.

Router(config)# no ip routing         Turns off IP routing function
Router(config)# interface fa0/0      Switches to FastEthernet interface
Router(config-if)# ip address address subnet_mask Assigns IP address and subnet mask to interface
Router(config-if)# no shutdown      Turns interface on
Router(config-if)# exit                     Returns to global configuration mode
Router(config)# ip default-gateway gateway_address Configures the default gateway
Router(config)# ip http server         Optional – starts http server process
===

12. You can connect GNS3 to real equipment, i have not done this yet myself, it is in the document attached how to do this.

13. When using windows 64 bit GNS3 will default to program files (x86). GNS3 is a 32 bit program for windows so point it to program files not the (x86).

14. I have a Lenovo Thinkpad with a i7 processor and 4GB of RAM. With 7 routers of the same type my processor is running between 8 and 15 %, my RAM consumption is around 2.3 to 2.8 GB. That is also using a few other programs on my laptop at the sometimes.

How Update DNS Records in Local Linux Machine - [ Ubuntu ]

Created Thursday 28 August 2014

By TDL Matias

***************************************************************
This tutorial is to use as my own keep track record of things I do everyday with Linux.. I had to install a new linux distro into a user computers, the distro in question was Ubuntu 12.04 - 64bit.

I have gave the machine a name = DevOps14 with IP 172.xx.xx.184 - The problem is that that same machine, had being installed on the intranet before with same hostname (DevOps14) and had assigned previously the IP address 172.xx.xx.185 ..

after installed, I tried to access it using the hostname, I was getting network names conflit errors ..

When I tried to ping it .. I was getting the following error ...


user@host1:~$ traceroute -n devops14.uk.domain
traceroute to devops14.uk.domain (172.xx.xx.185), 30 hops max, 60 byte packets
1 172.16.14.70 2996.257 ms !H 2996.201 ms !H 2996.180 ms !H

user@host1:~$ ping -c 3 devops14.uk.domain
PING devops14.uk.domain(172.xx.xx.185) 56(84) bytes of data.
From host1.uk.domain (172.xx.xx.xx) icmp_seq=1 Destination Host Unreachable
From host1.uk.domain (172.xx.xx.xx) icmp_seq=2 Destination Host Unreachable
From host1.uk.domain(172.xx.xx.xx) icmp_seq=3 Destination Host Unreachable


--- devops14.uk.domain ping statistics ---
3 packets transmitted, 0 received, +3 errors, 100% packet loss, time 2014ms


Then, I went and updated our DNS server records usind rndc tool ... Tried do ping the devops14 again .. but not avail ..


user@host1:~$ ping -c 3 devops14.uk.domain
PING devops14.uk.domain (172.xx.xx.185) 56(84) bytes of data.
From host1.uk.domain (172.xx.xx.xx) icmp_seq=1 Destination Host Unreachable
From host1.uk.domain (172.xx.xx.xx) icmp_seq=2 Destination Host Unreachable
From host1.uk.domain (172.xx.xx.xx) icmp_seq=3 Destination Host Unreachable


---devops14.uk.domain ping statistics ---
3 packets transmitted, 0 received, +3 errors, 100% packet loss, time 2000ms
pipe 3


Ok then ..IF I have updated the DNS - Records, theres no reason that I could not ping that machine right into the IP - 172.xx.xx.184 instead of 172.xx.xx.185 ... Something was no really adding up ...


So I went into https://www.google.com/ to investigate and se if someone had come accross the same issue it was then when I found in a Ubuntu forum [http://askubuntu.com/questions/414826/how-to-flush-dns-in-ubuntu-12-04 ]


That I had only to refresh the network DNS record on my local machine with this command.


user@host1:~$ sudo /etc/init.d/nscd restart
* Restarting Name Service Cache Daemon nscd                                                                      [ OK ]


And then PING it again ....


user@host1:~$ ping -c 3 devops14.uk.domain
PING devops14.uk.domain (172.xx.xx.184) 56(84) bytes of data.
64 bytes from devops14.local (172.xx.xx.184): icmp_seq=1 ttl=64 time=0.582 ms
64 bytes from devops14.local (172.xx.xx.184): icmp_seq=2 ttl=64 time=0.139 ms
64 bytes from devops14.local (172.xx.xx.184): icmp_seq=3 ttl=64 time=0.103 ms


---devops14.uk.domain ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms rtt min/avg/max/mdev = 0.103/0.274/0.582/0.218 ms



 All working fine now ... 

How to Allow MySQL Client to Connect to Remote MySQL server

Issue: How do I allow a MySQL client to connect to a MySQL database server?

Solution: By default, MySQL does not allow remote clients to connect to the MySQL database.
If you try to connect to a remote MySQL database from your client system, you will get the “Host is not allowed to connect to this MySQL server” message as shown below.

$ mysql -h 192.168.1.8 -u root -p
Enter password:
ERROR 1130: Host '192.168.1.4' is not allowed to connect to this MySQL server

You can also validate this by doing telnet to 3306 mysql port as shown below, which will also give the same “host is not allowed to connect to this MySQL server” error message.

$ telnet 192.168.1.8 3306
host 192.168.1.4 is not allowed to connect to this mysql server

If you want to allow a specific client ip-address (for example: 192.168.1.4) to access the MySQL database running on a server, you should execute the following command on the server that is running the MySQL database.

$ mysql -u root -p
Enter password:
mysql> use mysql
mysql> GRANT ALL ON *.* to root@'192.168.1.4' IDENTIFIED BY 'your-root-password';
mysql> FLUSH PRIVILEGES;

Also, update firewall rules to make sure port# 3306 is open on the server that is running the MySQL database.


After the above changes, when you try to connect to the MySQL database from a remote client, you’ll not get the “Host is not allowed to connect to this MySQL server” error message any more.

How Edit MySQL connection Error

    Cannot connect to MySQL server over network

Check /etc/my.cnf and make sure you are listening for outside connections. edit the line that starts with bind-address

change:

Code:

bind-address = 127.0.0.1

to:

Code:

#bind-address = 127.0.0.1

make sure mysql is running:

Code:

/etc/init.d/mysql status

if not, start it:

Code:

/etc/init.d/mysql start

check if the ubuntu firewall is running

Code:

sudo ufw status

if it is, allow mysql

Code:

sudo ufw allow mysql

    **************************************************************************

Possibly a security precaution. You could try adding a new administrator account: mysql> CREATE USER 'monty'@'localhost' IDENTIFIED BY 'some_pass'; mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'localhost' -> WITH GRANT OPTION; mysql> CREATE USER 'monty'@'%' IDENTIFIED BY 'some_pass'; mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%' -> WITH GRANT OPTION; Although as Pascal and others have noted it's not a great idea to have a user with this kind of access open to any IP. If you need an administrative user, use root, and leave it on localhost. For any other action specify exactly the privileges you need and limit the accessibility of the user as Pascal has suggest below. From the MySQL FAQ: If you cannot figure out why you get Access denied, remove from the user table all entries that have Host values containing wildcards (entries that contain '%' or '_' characters). A very common error is to insert a new entry with Host='%' and User='some_user', thinking that this allows you to specify localhost to connect from the same machine. The reason that this does not work is that the default privileges include an entry with Host='localhost' and User=''.  Because that entry has a Host value 'localhost' that is more specific than '%', it is used in preference to the new entry when connecting from localhost! The correct procedure is to insert a second entry with Host='localhost' and User='some_user', or to delete the entry with Host='localhost' and User=''. After deleting the entry, remember to issue a FLUSH PRIVILEGES statement to reload the grant tables. See also Section 5.4.4, “Access Control, Stage 1: Connection Verification”.

Having Problems to restart uBuntu 12.04 LTS workstation

Yesterday I have installed Ubuntu 12.04 on one of my testing workstations, orignally it came with Windows 7 pre-installed 2 SSD disks in a fake software Raid...

I have totatly removed Windows 7, deleted the partition and installed Ubuntu 12.04 LTS .. But, after installing Ubuntu the machine boots but do not show any signal of ubuntu ..

Its just a dark screen .. I tried to use live CD to repair the grub but with not avail...

Here is what I have from Ubuntu Boot repair tool --- >> I have taken off the script and guide to troubleshoot the ubuntu bootup, instead, I have place them into a file and you can download from and read it locally

Its hosted on Google drive here please download it !!... 

How to Install vsftpd on Ubuntu and Add New User

Warning: FTP is inherently insecure. If you must use FTP, consider securing your FTP connection with SSL/TLS. Otherwise, it is best to use SFTP, a secure alternative to FTP.

The first two letters of vsftpd stand for "very secure" and the program was built to have strongest protection against possible FTP vulnerabilities.

Step One—Install vsftpd

You can quickly install vsftpd on your virtual private server in the command line:

sudo apt-get install vsftpd

Once the file finishes downloading, the VSFTP will be on your droplet. Generally speaking, it is already configured with a reasonable amount of security. However, it does provide access on your VPS to anonymous users.

Step Two—Configure vsftpd

Once vsftpd is installed, you can adjust the configuration.

Open up the configuration file:

sudo nano /etc/vsftpd.conf

The biggest change you need to make is to switch the Anonymous_enable from YES to NO:

anonymous_enable=NO

Prior to this change, vsftpd allowed anonymous, unidentified users to access the server's files. This is useful if you are seeking to distribute information widely, but may be considered a serious security issue in most other cases.

After that, uncomment the local_enable option, changing it to yes and, additionally, allow the user to write to the directory.

local_enable=YES

write_enable=YES

Finish up by uncommenting command to chroot_local_user. When this line is set to Yes, all the local users will be jailed within their chroot and will be denied access to any other part of the server.

chroot_local_user=YES

Save and Exit that file.

Because of a recent vsftpd upgrade, vsftpd is "refusing to run with writable root inside chroot". A handy way to address this issue to is to take the following steps:

Create a new directory within the user's home directory

mkdir /home/username/files

Change the ownership of that file to root

chown root:root /home/username

Make all necessary changes within the "files" subdirectory

Then, as always, restart:

sudo service vsftpd restart

Step Three—Access the FTP server

Once you have installed the FTP server and configured it to your liking, you can now access it.

You can reach an FTP server in the browser by typing the domain name into the address bar and logging in with the appropriate ID. Keep in mind, you will only be able to access the user's home directory.

ftp://example.com

Alternatively, you can reach the FTP server on your virtual server through the command line by typing:

ftp example.com

Then you can use the word, "exit," to get out of the FTP shell.

Adding New Users To vsftpd

I found it rather strange that there arent any good tutorial that can explain how to add new users to vftpd. Google gives few results but most of them are trial and error method. So i decided to write this post after spending 1 hr trying to accomplish this simple task.

#edit /etc/vsftpd.conf or /opt/etc/vsftpd.conf
Open the vsftpd.conf file and search for chroot_list_enable=YES
Make sure it is YES. Do the same for the following variables
chroot_list_file=/etc/vsftpd.chroot_list or /opt/etc/vsftpd.chroot_list
chroot_list_enable=YES
Save and close the file

Create vsftpd.chroot_list in /etc/ or /opt/etc/
Add the username you want to export to ftp.
IMP: The user must already be a system user with a valid passwd. You must be able to find /home/
If the user you want to add is not a system user then create that user first before editing the above file.
#adduser 
#passwd 

Restart the vsftpd server using /etc/init.d/vsftpd restart or service vsftpd restart
Now you can log into ftp using the new user.

Read Media .vob Files on Ubuntu

Finally I figured out how to do it. These are the steps:

• Create a subdirectory called VIDEO_TS and move all files there.
• Create an DVD ISO file by executing:

genisoimage -iso-level 1 -dvd-video -volset-size 1 -o output.iso root_folder

• Mount the DVD ISO by executing:

sudo mount -t iso9660 -o loop output.iso /media/cd/

The result will be a compatible ISO image which can be played using any video player (Totem, MPlayer, Dragon, etc.).

For those ones who are too ubuntufied, you can use K3B to create a DVD project and select "Create image only" before burn it.

Anyway, thanks for the answers. This site is too different from what I was used to in StackOverflow though, I have to say. It seems that some of you just read the title of the questions before answering. Maybe my English is too bad :)

How to Change Office 2010 License Key

Issue: You go to activate Microsoft Office 2010 and you receive a message stating, “Your copy of Microsoft Office Professional Plus 2010 cannot be activated because the specified Product Key has already been activated the maximum number of times permitted for your software license as specified in the Microsoft Software License Terms.”

The solution is to change the product key to another product key. I will show you three different methods of changing the License Key

Method 1

Open “regedit”

Navigate the registry to: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\14.0\Registration\ and delete the whole “Registration” key located under the “14.0″ key

Right click “Registration”

Select “Delete”

Press “Yes”

Close Regedit, Restart an Office 2010 application. You should be prompted to reenter your License Key

Method 2

Open to Microsoft Word

Press “File”

Press “Help”

Select “Change Product Key” (this option was not here on my installation, I used Method 1)

Method 3

Click on Start Menu > Control Panel > Programs and Features (or Add/Remove Programs, depending on your operating system).

Click on your product, e.g. Microsoft Office Professional Plus 2010

Click “Change” on the top menu.

Select the option to “Enter a Product Key.”

Press “Continue”

Changing your Product Key

Once you complete one of the Methods listed above you should be able to change your Product Key

Enter the appropriate product key from the top of this page and click “Continue.”

Accept the agreement

Press “Continue”

Configuration will occur

Press “Close”

Select “I want to activate the software over the Internet (recommended)”

Press “Next”

Your product should activate successfully

Press “Close”