Cisco Router and Avaya Phone VPN example

!
!
!
ip local pool IPADDR_VPN_POOL x.x.x.x x.x.x.x
!
aaa new-model
!
aaa authentication login LETMEIN_GROUPx local
aaa authentication login userauthen local
aaa authorization network LETMEIN_GROUPx local
!
username AVAYAx1 password 0 xxxx1
username AVAYAx2 password 0 xxxx2
username AVAYAx3 password 0 xxxx3
username AVAYAx4 password 0 xxxx4
!
crypto isakmp policy 1
encr 3des
hash md5
authentication pre-share
group 2
!
crypto isakmp client configuration group LETMEIN_GROUPx
key $x$x$
pool IPADDR_VPN_POOL
pfs
!
crypto ipsec transform-set MYTSET_3DESx esp-3des esp-md5-hmac
!
crypto ipsec security-association lifetime seconds 86400
!
crypto dynamic-map dynmap2 20
set transform-set MYTSET
set pfs group2
reverse-route
!
crypto map clientmap client authentication list userauthen
crypto map clientmap isakmp authorization list groupauthor
crypto map clientmap client configuration address respond
!
!
interface XXX/XXX
ip address X.X.X.X X.X.X.X
!
crypto map clientmap

crypto map clientmap 20 ipsec-isakmp dynamic dynmap2
!

Mandatory, Supported, Disabled

The black and white from Cisco defines that the use of Data Rates options to specify the rates at which data can be transmitted between the access point and the client.

The data rates are available:

• 802.11a—6, 9, 12, 18, 24, 36, 48, and 54 Mbps

• 802.11b/g—1, 2, 5.5, 6, 9, 11, 12, 18, 24, 36, 48, or 54 Mbps

For each data rate, choose one of these options:

Mandatory—Clients must support this data rate in order to associate to an access point on the controller. Why force 11Mbps on an SSID, if not only to enforce better performance.

Supported—Any associated clients that support this data rate may communicate with the access point using that rate. However, the clients are not required to be able to use this rate in order to associate.

Disabled—The clients specify the data rates used for communication.

The notes say the clients must support and not operate at this rate and the supported option identifies a not required. I think I will attempt to test the overall enforcement and remove any ambiguity. I know this is one that I’ve always assumed what the options mean…

More to follow

Wireless Aerial Coverage

The following link was one I found when investigating the use of 1131AG access points. The positioning on a ceiling is certainly better qualified after reviewing this document.

http://www.cisco.com/en/US/prod/collateral/wireless/ps7183/ps469/product_data_sheet09186a008008883b.html

Securing RANCID CVSWEB

Update the 000-default file with the following details below to add basic authentication.

<VirtualHost *:80>

ServerAdmin webmaster@localhost

DocumentRoot /var/www

<Directory />

Options FollowSymLinks

AllowOverride None

order deny,allow

</Directory>

<Directory /var/www/>

Options Indexes FollowSymLinks MultiViews

AllowOverride none

order allow,deny

allow from all

</Directory>

ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/

        <Directory “/usr/lib/cgi-bin”>

                AuthType Basic

                AuthName “CVS REPO”

                AuthUserFile /etc/apache2/.htpasswd

                AllowOverride All

                Require valid-user

</Directory>

The command below will allow you to create a new user and it will lead you through adding a password for that user.

network@S-ABD-RANCID:$ sudo htpasswd -c .htpasswd myuser

Cisco ASA, IPSEC bypass options (bozo)

To permit ANY packets that come from an IPsec tunnel without checking any ACLs such as the OUTIDE_ACCESS_IN The following example enables IPsec traffic through the ASA without checking ACLs:

hostname(config)# sysopt connection permit-vpn

VTP (never use it) you need to know it

VLAN TRUNKING PROTOCOL is designed to ease administration  of a large number of switches. It manages addistions, deletions and renaming. You can only apply one VTP domain to a switch.

There are 3 versions of VTP and only two of those are actively used (V3 is CAT/OS). VTP is a method of synchronising the vlan databases of switches. The term domain is used to identify a cluster/group of switches. If the databases are to be shared then the domain name and any passwords set must match (not totally true, read below for more details).

VTP advertisements are based upon the revision number and are sent when a change is made or every 5 minutes. The advertisments are multicast frames.

A summary advertisment is sent out every 300 seconds and if a change occurs.

A subset advertisment after a configuration change. VLAN name, SAID value, type and MTU.

A request from client switch used to obtain up to date information.

Each change made to a vlan will increase the revision number. A switch will compare revision numbers when it receives an advertisement. A switch will overwrite its VTP database if the update from one of it’s peers is higher (potentially making an automatic change to the assigned vlan’s). The advertisement is forwarded onto any neighbours. If the switch receives a VTP advertisement with a lower revision it will reply with it’s advertisement to update it’s neighbour.

The roles are:

SERVER: This is the default and will allow the switch to create, delete and rename vlan’s.

CLIENT: Apparently clients cannot make changes. However, I have seen events where client switches have been able to pass on updates to server peers.

TRANSPARENT: Allows the creation, deletion and renaming vlan’s but all information remains local. This mode will forward VTP information to its peers.

The use of show vtp status identifies the version in use, the revision number and the number of vlans that are being passed around via VTP.

Q-in-Q VLAN tunnels

Q-in-Q allows already tagged frames across a network by tunnelling them inside a single vlan. The process adds a second 802.1Q tag to each frame. As the packets traverse the network the network the infrastructure see’s the outside tag and forwards based on that vlan. Q-in-Q tunnels are usually implemented by service providers to encapsulate a customers multiple vlans into a single vlan.

Eg: as a simple example

Customer vlans 1,2,3,4,5
Service provider vlan 100

Customer switch trunk vlans 1-5 —-> (service provider dot1q-tunnel vlan 100) ——> vlans 1-5

This is enabled with:

switchport mode dot1q-tunnel

The tunnel interfaces should be setup at either end of the overall link.

VLAN trunks

ISL: Cisco proprietary and encapsulates the original frame in a 26 byte header and a 4 byte trailer. The ISL vlan’s are 1-1001.

802.1Q: Open standard and inserts a field in the 802.1P header, just after the source mac-address. The 802.1Q vlan’s are 0-4094.

If a mixture of ISL and 802.1Q is in use then the matching vlan’s can map across up to the ISL limit.

Points to note include if a non trunking port receives and ISL encapsulated frame then the frame is dropped. This is because the header and trailer cause the frame to exceed the MTU and may be counted as an error.
If an 802.1Q frame is received on a non trunking port then the source and destination mac-addresses are checked and the frame is switched normally at Layer2.

Dynamic Trunking

DTP sends out adverisments every 30 seconds and ports can become a trunk either by configuration or dynamically. A port can be in one of five modes:

ACCESS: A user port in a single clan.

TRUNK: A port has negotiated its a trunk with its peer.

NON-NEGOTIATE: The port is a trunk and does not negotiate with any peers.

DYNAMIC DESIRABLE: Dynamically negotiates with its peer and will become a trunk if the other end is set to trunk,dynamic desirable or dynamic auto.

DYNAMIC AUTO: Passively waits to negotiate DTP with its peer. The peer must be configured as a trunk or dynamic desirable.

Cisco LWAP conversion from AP to LWAP

The process of upgrading/downgrading the AP/LAP’s can be covered as with most networking in many ways. This method is one of my favourites and allows you to copy the code off of an existing LWAP node.

To copy off of an LWAP node:

archive upload-sw tftp:///c1130-rcvk9w8-mx.DEFAULT

Download IOS onto the device:

archive download-sw /force-reload /overwrite tftp:///c1130-rcvk9w8-mx.DEFAULT

There really was a Cisco Caravan…

Amir Mohammed, Henning Speckels, Nigel Sims, Julian Shead, Alastair Read, Paul Stayt, Jonathan Myers, Aaron Milton-Eldridge, Peter Massey.

Cisco ACE resetting the default passwords

Follow these steps to reset the password that allows the Admin user access to the ACE module:

Connect to the console port of the ACE module in the Catalyst 6500 series switch.

Reboot the ACE module from the Catalyst 6500 series CLI.

“no power enable module x”

“power enable module x”

During the bootup process, Press ESC when the “Waiting for 3 seconds to enter setup mode…” message appears on the terminal (see the example below). If you miss the time window, wait for the ACE module to properly complete booting, reboot the ACE module from the Catalyst 6500 series CLI, and try again to access the setup mode by pressing ESC.  The setup mode prompts if you want to reset the admin password. Enter y. The “Resetting admin password to factory default” message appears. The ACE module deletes the admin user password configuration from the startup configuration and resets the password back to the factory default value of admin.

<<abridged>>

Starting lcpfw process…

inserting IPCP klm

Warning: loading /itasca/klm/klm_session.klm will taint the kernel: no license

See http://www.tux.org/lkml/#export-tainted for information about tainted modules

Module klm_session.klm loaded, with warnings

inserting cpu_util klm

create dev node as ‘mknod /dev/cpu_util c 236 0’

getting cpu_util dev major num

making new cpu_util dev node

Session Agent waiting for packets .

Waiting for 3 seconds to enter setup mode…

Entering setup sequence…

Reset Admin password [y/n] (default: n): y

Resetting admin password to factory default…

XR Serial driver version 1.0 (2004-11-08) with no serial options enabled

<<abridged>>

Loading.. Please wait…Done!!!

The boot process continues as normal and you are able to enter the admin password at the login prompt.

Linux set local proxy for O/S

export http_proxy=http://:port

3750-X route-map for wireless access

!

interface Vlan100

ip address 172.16.255.254 255.255.0.0

ip helper-address 172.16.255.250

ip pim sparse-mode

ip policy route-map ROUTE-PROXY-TRAFFIC-POLICY

!

!

access-list 101 permit tcp 172.16.1.0 0.0.0.255 any eq www

access-list 101 permit tcp 172.16.1.0 0.0.0.255 any eq 443

!

!

access-list 102 permit ip 172.16.1.0 0.0.0.255 any eq 50

access-list 102 permit ip 172.16.1.0 0.0.0.255 any eq 51

access-list 102 permit udp 172.16.1.0 0.0.0.255 any eq 500

access-list 102 permit udp 172.16.1.0 0.0.0.255 any eq 4500

!

!

!

route-map ROUTE-PROXY-TRAFFIC-POLICY permit 10

match ip address 102

set ip next-hop 172.16.255.253

!

route-map ROUTE-PROXY-TRAFFIC-POLICY permit 50

match ip address 101

set ip next-hop 172.16.255.252

Visio Auto-Connect

If you actively use visio and are fed-up of the auto-connect as much as I was.. this is for you!

Enable or disable AutoConnect in all drawings

1. On the Tools menu, click Options.
2. Click the General tab.
3. Under Drawing window options, select the Enable AutoConnect check box.

Banner MOTD #

A banner should be an informational warning/notification and not be a welcome to my device. I love a good banner and ascii, makes it all the more fun.

banner motd #
_~_
. / ^ -\ .
|\| (o) (o) |/|
|—–.OOOo–U–oOOO.——————|
|                                      |
|   * Authorised Access Only *       |
|                                      |
|_______________Oooo.__________________|
.oooO           (   )
(   )            ) /
\ (            (_/
\_)

This host is: $(hostname)

#
!

Cisco WLC 7.x future Wireless QOS capabilities

Having the need to look at a converged network/telephony strategy with Microsoft LYNC and a request (not requirement) for users to be able to access the LYNC telephony over a Cisco wireless solution. Thinking a little out of the box I had got to the point of considering how to run ATM over a lightweight solution.

Along came AVC.. it certainly looks like a great step forward and I cant wait to have an opportunity to plau.

http://www.youtube.com/watch?feature=player_detailpage&v=h6ZLSc_lYEg

http://www.cisco.com/en/US/solutions/collateral/ns1015/ns483/ns780/at_a_glance_c45-649117.pdf

 

 

Cisco ASA ASDM logging filters

I was looking at applying some filters to the ASDM logging viewer the other day and spent 5 minutes adding one of each type just to see what would be seen within the configuration. Its pretty straight forward and very similar to Wireshark filters. Nb. the use of a “;” where multiple filters are applied.

ASA Firewall Filters:

# Only source IP: FILTER:srcIP=172.16.0.50
# Only port 21: FILTER:srcPort=21;
# Source IP and port 21: FILTER:srcIP=172.16.0.50;FILTER:srcPort=21;
# Destination IP: FILTER:dstIP=10.206.164.41;
# Severity Level (4=WARNINGS): FILTER:sev=4;

Export Netflow over IPSEC

One of my earlier posts covered routing Netflow Exports to a server over IPSEC. The previous covered method relied on the use of GRE tunnels and loopback interfaces to forward the export to a central router which in-turn then forwarded them onto the collector.

The question of why bother and just not use a Cisco ASA to terminate the VPN could be raised and I guess the requirements and the methods of the outgoing connectivity will have input. However, the ASA will support the exporting of Netflow over and IPSEC tunnel and adding no funky workarounds. The two key things to remember are:

Add the collector to your INSIDE interface

Ensure the collector is covered by Interesting traff