Posts

Showing posts from 2010

Module 1 Lesson 3: STP

Used to prevent layer 2 bridging loops PVST+ default - One STP instance per VLAN - Cisco proprietary Phase I - Root Bridge Election - "root" of the spanning-tree - Election based on BID - Bridge Priority - MAC Address Phase II - Root Port Election - Upstream port closest to root bridge. STP ROOT PORT ELECTION - Upstream port closest to root bridge - Root port election based on - Lowest cumulative cost - Inverse value based on interface bandwidth - Lowest upstream BID - Used to isolate multiple connections to upstream same bridge - Lowest port ID - Lowest port priority - Lowest port number Portfast - Forward through listening and learning phases BPDU Filter - If BPDU is received revert out of portast state BPDU Guard - If BPDU is received shut port down Root Guard - If superior BPDU is received shut port down Uplinkfast - Immediately transition alternate ports to forwarding when root port is lost BackboneFast - Expire max age when inferior BPDU

BGP Communities

Community Attribute The community attribute provides a way of grouping destinations, called communities, to which routing decisions (such as acceptance, preference, and redistribution) can be applied. Use route-maps to set them. no-export - Do not advertise this route to EBGP peers. no-advertise - Do not advertise this route to any peer. internet - Advertise this route to the Internet community; all routers in the network belong to it.

P90X Day 1

I went home from work and got the kids to bed. As 8:00 was approaching I was kinda dreading it because I wanted to watch some Chuck and the 2 hour episode of 24. I waited for my brother in-law to show up with the disks. He finally called about 8:30 and said he wasn't coming. So to recap day 1 I went home ate some mint chocolate chip ice cream and watch Chuck and 24. My disks will arrive in the mail this week so I will for sure start when they get to my house. And for all my l33t friends yes I know I can get them from a torrent or Usenet. I figured if I am going to have abs of steal and have my wife iron her clothes on them I should give Tony something.

P90X

We keep watching this P90x Infomercial on Tv and see these people totally ripped. All it takes is 90 days for 1 hour a day. We are going to test this for proof of concept. We will start tonight. And post pictures every 15 days along with weight. Wish us luck!

EIGRP Adjaceny Authentication

1st thing first. With any Authentication you must set your clock to be the same on every router. clock set 10:21:00 April 4 2010 Next create your keychain (Key Number must Match) key chain EIGRP key 1 key-string CISCO123 Next apply your keychain Go to the interface you want to authenticate and specify that you want authentication to be used. ip authentication mode eigrp 100 md5 (This turns on authentication) Next identify the keychain you wish to use. ip authentication key-chain eigrp 100 EIGRP ****Extra Options**** ! key chain EIGRP key 1 key-string CISCO123 accept-lifetime 00:00:00 Jan 1 1993 00:15:00 Jan 1 2007 send-lifetime 00:00:00 Jan 1 1993 00:00:00 Jan 1 2007 key 2 key-string CISCO456 accept-lifetime 23:45:00 Dec 31 2006 infinite send-lifetime 00:00:00 Jan 1 2007 infinite !

EIGRP Unequal-Cost Load-Balancing

Unequal-Cost Load-Balancing is when you have 2 paths to the same destination with different Bandwidths. If you have 1 path that is 64Kbps and another path that is 256Kbps then you have to use the Variance command to accomplish this in EIGRP. All you have to do is take 256Kbps/64Kbps and you get 4. So the Variance is 4. Router#Conf t Router#Router Eigrp 100 Router#variance 4

EIGRP Timers

EIGRP sends hello packets every 5 seconds on high bandwidth links and every 60 seconds on low bandwidth multipoint links. 5-second hello: broadcast media, such as Ethernet, Token Ring, and FDDI point-to-point serial links, such as PPP or HDLC leased circuits, Frame Relay point-to-point subinterfaces, and ATM point-to-point subinterface high bandwidth (greater than T1) multipoint circuits, such as ISDN PRI and Frame Relay 60-second hello: multipoint circuits T1 bandwidth or slower, such as Frame Relay multipoint interfaces, ATM multipoint interfaces, ATM switched virtual circuits, and ISDN BRIs To change the timers issue these commands on the interfaces. ip hello-interval eigrp ip hold-time eigrp

Hector Runs Over a Cat

Image
Hector informed me today that he ran over a cat. I asked him if he stopped and he said "I slowed down". I asked him if he was going to bury it but he would not. I then gave him a ride home and pulled up next to the 3 day dead mangled cat and Hector wouldnt look at it. I took a picture and MMS him so he could see what he had done to this poor defenseless animal. I offered to help him bury it but he just seems so callus. I am posting this picture to try to get Hector to help me bury this cat. Please post your thoughts and suggestion for Hector. I think he just needs a hug.

Private VLANs

Image
Private VLANs When you configure private VLANS, the switch must be in VTP transparent mode. You Need a Primary VLAN and a Secondary VLAN There are two types of secondary VLANs: Isolated VLANs - Ports within an isolated VLAN cannot communicate with each other at the Layer 2 level. Community VLANs - Ports within a community VLAN can communicate with each other but cannot communicate with ports in other communities at the Layer 2 level. Private VLANs provide Layer 2 isolation between ports within the same private VLAN. Private-VLAN ports are access ports that are one of these types: Promiscuous - A promiscuous port belongs to the primary VLAN and can communicate with all interfaces, including the community and isolated host ports that belong to the secondary VLANs associated with the primary VLAN. Isolated - An isolated port is a host port that belongs to an isolated secondary VLAN. It has complete Layer 2 separation from other ports within the same private VLAN, except for the promiscuou

MSTP

MSTP All switches need this: spanning-tree mst configuration instance 1 vlan 1-3 instance 2 vlan 4-6 instance 3 vlan 7-9 Root Needs this: spanning-tree mst 1-3 root primary

Spanning Tree

Image
Cisco PVST+ 802.1d Root Bridge Elect Root Bridge -> Lowest Bridge ID Bridge ID -> Priority + MAC All ports on the Root Bridge are Designated ports and are in a Forwarding State. Root Bridge is the Reference Point for everyone else. Each switch in the network looks for the best path to the root bridge. Decision is made based on the path cost. If the path cost is the same Port ID breaks tie. All other ports towards the Root Bridge are put in Blocking/Alternate state. Path Cost Ethernet = 100 Fast Ethernet = 19 Gigabit = 4 10 Gigabit = 2 Port States - Convergence takes 50 seconds Disabled Blocking - 20 seconds Listening - 15 seconds Learning - 15 seconds Forwarding Network Changes BPDUs - Hello timer is sent every 2 seconds TCNs are sent up stream to each device notifing the switch of a change in the topology. TCAs are sent back down stream to acknowledge the changes. This is done untill the TCN reaches the Root Bridge. Rapid PVST+ 802.1w Root Bridge Elected the same way as 802.1d P