Posts tagged Cisco
I got this over at Networking-Forum.com, a member named Fred created it, he was even kind enough to provide the Visio diagram, IP scheme spreadsheet and, most importantly, the .net file for Dynagen/GNS3. I spent a lot of my Saturday working on this beast. I thought I should share it here as it is great practice for MPLS VPNs and BGP along with some OSPF, NAT, IPSEC and GRE exposure.
* The two Internet routers should serve as transit AS’s. No other routers should permit transit traffic.
* Internet sites (modeled by loopbacks) should be accessible by all lan IP’s.
In this article I’ll go over how to build a SIP Trunk to a provider with Call Manager Express, in this case we’ll use Flowroute. I will be using my 3725 with IOS “c3725-adventerprisek9-mz.124-15.T10.bin”.
First we will enable SIP, then we configure the router to register with our provider, then we’ll configure our codecs and dial peer, finally we’ll go over some show commands to verify that everything works.
Here’s how to enable SIP:
voice service voip sip
Very simple, we just enable the SIP protocol.
Next we configure our router to register with Flowroute:
sip-ua authentication username xxxxx password 7 xxxxxxxxxx realm sip.flowroute.com calling-info pstn-to-sip from number set 1xxx7325736 no remote-party-id registrar dns:sip.flowroute.com expires 3600
This tells the router to register with “sip.flowroute.com” using the username and password we specified.
Next we configure our codecs:
voice class codec 1 codec preference 1 g729r8 codec preference 2 g711ulaw codec preference 3 g711alaw
Here we specify which codecs we want to use and what order we prefer them, 1 being most preferred and 3 being least preferred. I have chosen to use g729 whenever possible as it needs much less bandwidth and sounds great.
What is PeerIX:
PeerIX is a project a bunch of other nerds and I are working on. Most of us know each other from HardForum and/or Networking-Forum. The idea is to develop a functional “mini-internet” to learn and gain experience with enterprise and service provider technologies.
What are the requirements?
A network device that supports IPsec, GRE and BGP. Other routing protocols may be considered but will be “corner case” as the core will be eBGP.
What devices work?
Currently most Cisco routers will work permitted that you are running an IOS that supports the core technologies above.
You can use the IOS feature navigator to verify if your IOS/device supports the required features.
What technologies are you talking about?
The sky is the limit here, but the main core technologies are IPSec, GRE and BGP. Right now we have limited things going on within this network but eventually the hope is to grow it much larger with more services.
This is just a quick post about an awesome little command I just saw on Networking-Forum. The command is “default interface”. First we’ll look at an interface config:
CORE#sh run int gi0/32 [...] interface GigabitEthernet0/32 switchport access vlan 10 switchport mode access spanning-tree portfast end
Now we’ll run the command:
CORE(config)#default interface GigabitEthernet0/32 Interface GigabitEthernet0/32 set to default configuration
CORE#sh run int gi0/32 [...] interface GigabitEthernet0/32 end
You can also use this with the “interface range” command if you want to reset a bunch of ports to their default settings. Simple little command with a lot of power.
In this short article we will configure some Layer 2 EtherChannel links. These are used to aggregate switchports to increase bandwidth and provide redundancy. I am running a four port EtherChannel from my Edge router to my Core switch. This article is useful for CCNP (BCMSN) studies.
First we will configure our switchports, then we will configure the Port-Channel interface, then we’ll look at some show commands.
Here is the switchport configuration:
interface range GigabitEthernet0/23 - 26 switchport trunk encapsulation dot1q switchport trunk native vlan 10 switchport mode trunk channel-group 1 mode on
We’ve set the trunking encapsulation to 802.1q and turn trunking on, then we set the native VLAN (I use 10), the command to note is “channel-group”, we have made the group 1 and set the mode to “on”, this means the port will not negotiate to become an EtherChannel, it just is.
Next we configure the Port-Channel interface:
interface Port-channel1 switchport trunk encapsulation dot1q switchport trunk native vlan 10 switchport mode trunk
This is just a logical interface (somewhat similar to a Loopback). We do the same trunk configuration here.