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Netios 0.73

Netios 0.73 fixes some bugs and

Complete changelog :

2010-02-10  (0.73) Jean-Christophe Baptiste <jc@phocean.net>

* remove useless options
* fix various bugs

Check there (tools page) for more details and a download link.

Netios 0.72

Netios 0.72 fixes some bugs with the show_run mode and large config files. I also found some issues concerning the prompt detection, so it should be fixed now.

Complete changelog :

2010-01-14  (0.72) Jean-Christophe Baptiste <jc@phocean.net>

* ciscoclass.py : forgot to remove a debug print
* ciscoclass.py : finish and fix a bunch of bugs in the show run function, format the config file properly
* ciscoclass.py : fix the prompt regex

Check there (tools page) for more details and a download link.

Netios 0.71

I release a new version of Netios : 0.71.

There are a lot of changes, starting with cosmetics, but the biggest one is the support of multiprocessing.

It is now able to process several routers at the same time, so using it on a large list of machines results in a big speed up.

A downside is that it now requires at least Python 2.6, as multiprocessing started to be supported with this version only. Most Linux distributions now include Python 2.6, but still not all. Anyway it will be more and more the case. If you can’t uprade your distribution, you can stick with 0.60 which still do most of the work fine.

It is also now able to fetch a configuration file remotly, but it requires more testing before I feel confident in the way it works.

The complete changelog :

2009-12-20  (0.71) Jean-Christophe Baptiste ;

* ciscoclass.py : handle correctly the cisco pager — More — so that “show run” mode should work even with large config files
* sshclass.py : allow to override terminal size system settings (make use of the cisco pager to avoid filling the buffer)

2009-11-16  (0.70) Jean-Christophe Baptiste (private release)

* implement multiprocessing
* improve code documentation
* clean up UI
* reduce useless logging
* netios.py : bug : missing startTime parameter in f_skip_error and f_command functions

I cross my fingers so that there are not too many bugs, but if so, please don’t forget to report it to me.

Check there (tools page) for more details and a download link.

Netios

I just released an alpha release of a little tool that may help network administrators with a large park of Cisco routers or switches :

Netios is a little tool aimed to help network administrators to administrate a large number of Cisco network devices.
Providing it with a list of equipments, it connects within SSH to remotly apply IOS commands.

It can automatically :

  • retrieve and export in a CSV file the list of local users
  • update the local user, the enable password
  • change NTP settings
  • execute a file of customed IOS commands
  • retrieve configuration files

It can read the targets from the command line or from a text file.

Its primary goal is to improve the security by making it easier to renew regularly the local password of these equipments, but it can do more convenient things (and I will continue to work to add more of them).

Check there (tools page) for more details and a download link.

Cisco configuration buffer full

I got this weired message while trying to save a configuration :

#wr mem
Building configuration...
% Warning: Saving this config to nvram may corrupt any network management or security files stored at the end of nvram.
Continue? [no]: no
% Configuration buffer full, can't add command:
************************************************************************

Looks scary at first, but normally it should be solved with a single command :

# configure terminal
(config-ter)# service compress-config
(config-ter)# end
# write mem

I guess that there are little chances the issue remains after that, but if so, well, you may be in trouble…

IOS : Configuration buffer full, can’t add command

This error message suddenly showed up on one of my router when I tried to save its running configuration.

service compress-config allowed me to workaround this buffer problem :

router#wr mem
Building configuration...

% Warning: Saving this config to nvram may corrupt any network management or security files stored at the end of nvram.
Continue? [no]: no
% Configuration buffer full, can't add command:
************************************************************************

%Aborting Save. Compress the config.[OK]
router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
router(config)#service compress-config
router(config)#exit
router#wr mem
Building configuration...
Compressed configuration from 21787 bytes to 7991 bytes[OK]

Practicing Cisco networking with GNS3 and Dynamips

GNS3 and Dynamips put together give a nice open-source and free alternative to emulate a network with IOS routers. Dynampis is an emulator of Cisco 7200 router, while GNS3 provides a nice graphical environment to design your network and use the virtual routers.

I sometimes use Boson Netsim, which is not only non-free but not so reliable.

However, as I just started to use GNS3 and Dynamips, I don’t know it so well yet and won’t compare any further the two solutions.

On this page, I am just summarizing the few steps to set it up on your Linux system.

First, set up the prerequisite :

$ aptitude install python-qt4

Now, go to gns3.net and download the source code for Linux (direct link).

You may extract the archive in your local application folder :

$ wget http://pfe.epitech.net/frs/download.php/819/GNS3-0.5-src.tar.gz
$ tar -xzvf GNS3-0.5-src.tar.gz -C /opt

Then, you need the dynamips binary from the dynamips blog (direct links for x86 or amd64 platforms).
The file must be executable.

$ wget http://www.ipflow.utc.fr/dynamips/dynamips-0.2.8-RC2-amd64.bin
$ chmod u+x dynamips*.bin
$ mv dynamips-0.2.8-RC2-amd64.bin /opt

Now, start GNS3 :

$ /opt/GNS3-0.5-src/gns3

In the edit menu, select preferences and go the dynamips section.

Just browse to the dynamips binary you dowloaded, to fill the value of the executable path field.

Still from the edit menu, select IOS images and hypervisors. There, you have to add all the IOS images you want to use, one after another. Normally, the default settings for each file loaded are suitable.

Back to the main window, you can drag and drop routers and link them, creating the topology you wish.

For now, just add one router. Right click on it and select start to start it up. Right click again and select console.

Enjoy ! Of course, I strongly recommand that you start reading further from this page.

Resources :

http://www.ipflow.utc.fr/blog/
http://www.gns3.net/
http://www.blindhog.net/tutorials/gns3-linux-install/gns3-linux-install.html

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