New year ....... blah blah blah

After lots of thought and consideration I decided to leave Cisco at the end of last year. It wasn't easy, especially because of some of the people I had been working with! However for my own career development and enjoyment I have decided to join Pivotal. This is a very…

VDC (Virtual Device Contexts)

The Nexus 7000 supports VDC. VDC allows the partitioning of a single physical device into multiple logical devices.The logical separation provides the following benefits; Admin and management separation Change and failure domain isolation from other VDC Address, VLAN, VRF and vPC isolation Each VDC appears as a unique device…

OTV (Overlay Transport Virtulisation)

Overlay Transport Virtulisation (OTV) is currently a feature on the Nexus 7000 product (M1 modules) range that provides DCI (Data Center Interconnect). It allows multiple data centers to be linked together and extends L2 Ethernet across them. OTV is different to EoMPLS & VPLS as a LAN extension technologies. It…

Nexus

I probably should have made notes on the Cisco Nexus platform and its features when I first started playing with them back in 2010/2011, it would have saved me running over it again and making new notes. Although quite a few new features have been introduced since then Key…

EIGRP

Network statement does not control what networks are being advertised but instead what interfaces are running EIGRP process Uses protocol number 88 Multicast to 224.0.0.10 (TTL=0) Receiving neighbour unicasts are acknowledged Unequal cost load sharing of up to 16 links EIGRP does not form neighbours over…

ODR

In a small hub and spoke (where spokes are stubs) you could use On Demand Routing (ODR) to achieve full readability between sites. ODR uses CDP as its transport . CDP versions must match. ODR will auto-inject a default route in the spoke routers and the spoke routers will advertise their…

HTTP

To configure HTTP on Cisco IOS; ip http server ip http access-class <ACL> ip http authentication aaa aaa authentication login default local ip http max-connections <number> ip http port <TCP port no> ip http timeout-policy idle <sec> life <sec> requests…

GLBP

Provides gateway redundancy by using a singe IP and multiple MAC Can be 4 routers in a group Group members communicate to 224.0.0.102 on UDP-3222 Hello messages sent every 3 seconds by default Group members will elect a Active Virtual Gateway (AVG), the other routers will be…

VRRP (Cisco)

interface fa0/1 vrrp 1 ip 1.1.1.1 vrrp 1 priority 200 vrrp 1 advertise #advertisement timer in seconds vrrp 1 timer learn #learns timer from master router vrrp 1 authentication vrrp 1 description no vrrp 1 preempt #preempt is on by default with VRRP show vrrp show…