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NTP client / server with authentication

SERVER CONFIG

ntp authentication-key 1 md5 0802657D2A36 7
ntp master 5

CLIENT CONFIG

ntp authentication-key 1 md5 1531223F2705 7
ntp authenticate
ntp trusted-key 1
ntp server 10.0.12.1 key 1

Notes: the client authenticates the time source, server must have the key.

Cisco Live! Europe: I'm in!

First time here, the impression is like being in the Willy Wonka chocolate factory with the big difference you can touch everything without disappear.

As my job is not focused on a single technology I'm registered to many different sessions, from WiFi to Security, from FCoE to …

The dscp mutation map is a per-port configuration that permits to modify the dscp field of a packet. The mutation map works for EGRESS traffic only

We trust the documentation but it's event better to verify it.

The topology si simple:

PC1 11.0.0.1 --> G1/0/1 C3750-24 G1/0/24 --> G1/0/24 C3750-48 G1/0/1 --> …

Private VLAN configuration:

vlan 300
private-vlan primary
private-vlan association 301-302
!
vlan 301
private-vlan isolated
!
vlan 302
private-vlan community

Port configuration:

interface GigabitEthernet1/0/1
	switchport private-vlan host-association 300 301
	switchport mode private-vlan host

What about the SVI? …

Netflow quick notes for basic config.

NETFLOW EXPORT

Send NetFlow data to a collector:

• From? (source)
• Where? (destination, port)
• How? (udp, sctp, backup)
• Version? (1,5,9)

SAMPLING / FILTERING

Not all traffic is evaluated to generate NetFlow statistics. Sampling (one packet each N) of filtering (sampling only on a …

Your Route to Cisco Career Success  by Kevin Wallace

A free ebook from Amazon/Kindle about the strategy to prepare for a brilliant career in networking.

UPDATE: the book was free just for a limited amount of time (I got the link from Twitter).

After one week of training in Milan and passing the exam I've added an Alcatel-Lucent certification to my c.v.:

"Alcatel-Lucent Certified Field Expert - ACFE - OmniSwitch R6/R6"

OmniSwitch have some proprietary features, like mobile vlans, that may be very useful in some deployments. The new 10K platform with …

This week I'm attending an HP training in Milan.

The course topics aren't as challenging as I've expected but I had the opportunity to test focus on some interoperability problems that may occur in mixed environments, especially with Cisco and non-Cisco devices, like PVST.

For this post we use 2 switches, a Cisco and a …

A great blog and Youtube channel with a lot of resources for Cisco Wireless:

When a router config is saved with

copy run start

IOS asks for a destination filename:

RTR#copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]

To bypass the request and use the default name startup-config do this:

RTR(config)#file prompt quiet

And then again

copy …

OSPF Forward Address (FA):

• works like BGP next-hop for OSPF external routes

• advertised only if next-hop is on a not-passive and multiaccess interface

• if there's not a route to FA address, route is not installed

• FA = 0.0.0.0 --> cost to ABR

• FA <> 0.0.0.0 --> cost to FA address

• NSSA --> FA is …