The first script is used to configure 61 Cisco Catalyst 2960S access switches for DHCP Snooping in a way that every switch builds the DHCP Snooping database with its own hostname on the FTP server so that different databases do not overwrite each other.
- EIGRP Process
- EIGRP Terminology
- EIGRP Packets
- EIGRP Tables
- EIGRP Timers
- Passive Interface
- EIGRP Re-convergence Process
- Stub Routers
- Split Horizon
- EIGRP Bandwidth Control
- EIGRP Load Balancing
- Route Filtering
- Route Summarization
- Default Routing
- EIGRP Feature Summary
- BPDU Frame
- STP (802.1d) Process Phases
- STP Port States
- STP Topology Changes
- STP Re-convergence Process
- Optimizing STP Re-convergence
- Protecting STP Topology
- STP and VLANs (CST, PVST+, MST)
Bridging loops forward a single frame around and around between switches forever.
STP prevents bridging loops by forming a spanning-tree topology in a layer 2 network with redundant links.
STP uses a special layer 2 frame called BPDU to operate.
|Cisco Proprietary||IETF Standard||Cisco Proprietary|
|Active / Standby||Master / Backup||Active Virtual Gateway (AVG)
Active Virtual Forwarders (AVF)
· AVG assigns virtual MAC addresses to each AVF and answers ARP requests.
· AVFs forward the traffic.
|Active router selection by priority. The higher, the better.
|Master router selection by priority. The higher, the better.
|Active Virtual Gateway selection by Priority/IP Address in group. The higher, the better.
|Group number (0~255) but usually 16 groups are supported.
HSRP group number is locally significant on interfaces.
|Group number (1~255)||Group number (0~1023)|
|HSRP Hello packets
MC: 126.96.36.199 / UDP: 1945
|VRRP Hello packets
|GLBP Hello packets
MC: 188.8.131.52 / UDP:3222
Hello/Dead time= 3/10 s Default
|No preemption by default.||Preemption by default.||No preemption by default.|
HSRP decreases the priority (default=10)
VRRP decreases the priority
GLBP decreases the weighting
XX= HSRP group in hex
XX= VRRP group in hex
x…x= Group number in bin
YY= GLBP Forwarder Number in hex
|Authentication: MD5/Text||Authentication: MD5/Text||Authentication: MD5/Text|
|No load balancing||No load balancing||Load balancing|