Notes: Managing vlan.dat in Cisco Catalyst Switches Running Cisco IOS Software

underay — Mon, 18 May 2009 04:29:14 +0000

VLAN or VTP configuration changes in CatOS are written to NVRAM immediately after a change is made. In contrast, Cisco IOS software does not save configuration changes to NVRAM unless you issue the copy run start command.

VTP client and server systems require VTP updates from other VTP servers to be immediately saved in NVRAM without user intervention. The VTP update requirements are met by the default CatOS operation, but the Cisco IOS software update model requires an alternative update operation. For this, a VLAN database was introduced to Cisco IOS software for Catalyst switches as a method to immediately save VTP updates for VTP clients and servers. This VLAN database is in the form of a separate file in NVRAM called the vlan.dat file.

During boot up, the switch compares the content in the vlan.dat file and the configuration in startup-config to determine if it should use the configuration in vlan.dat or startup-config. When you save VTP mode, domain name, and VLAN configurations in the switch startup configuration file and reboot the switch, the VTP and VLAN configurations are selected by these conditions:

If both the VLAN database and the configuration file show the VTP mode as transparent and the VTP domain names match, the VLAN database is ignored. The VTP and VLAN configurations in the startup configuration file are used. The VLAN database revision number remains unchanged in the VLAN database.

If the startup VTP mode is server mode, or the startup VTP mode or domain names do not match the VLAN database, VTP mode and VLAN configuration for the first 1005 VLANs are selected by VLAN database information, such as the vlan.dat file. VLANs greater than 1005 are configured from the switch configuration file.

Full document: http://www.cisco.com/en/US/products/hw/switches/ps5213/products_tech_note09186a0080a49dbf.shtml

New Cisco Document: ASA/PIX 8.x: Site-to-Site IPSec VPN Authentication Using Digital Certificates with Microsoft CA Configuration Example

underay — Mon, 27 Apr 2009 11:45:29 +0000

The new improved version of the document describes the procedures related to CA (more nice screenshots:)) and an example of the use of named rsa keys on ASA

Here is the link

Release of the New Cisco SAFE Security Architecture

underay — Fri, 24 Apr 2009 11:56:25 +0000

The new release of SAFE includes validated design guides for Data Center, Campus, Management, WAN Edge, Extranet, Internet Edge, E-Commerce, Branches, Partner Sites, Teleworkers, and the Core Network Foundation. There are also additional updates to SAFE on our roadmap, including SAFE for UC, Mobility, Identity, etc.

New Cisco SAFE Security reference guide is available for download

New Cisco SAFE poster

Count to my lab

underay — Mon, 20 Apr 2009 22:39:48 +0000

Notes from Betelgeuse 7

Notes: Managing vlan.dat in Cisco Catalyst Switches Running Cisco IOS Software

New Cisco Document: ASA/PIX 8.x: Site-to-Site IPSec VPN Authentication Using Digital Certificates with Microsoft CA Configuration Example

Release of the New Cisco SAFE Security Architecture

Count to my lab