Learn Cisco Network Administration in a Month of Lunches

Learn Cisco Network Administration
brief contents
contents
preface
acknowledgments
about this book
About the code
Author Online
about the author
1 Before you begin
1.1 Is this book for you?
1.2 How to use this book
1.2.1 The main chapters
1.2.2 Hands-on labs
1.2.3 Further exploration
1.2.4 Above and beyond
1.3 Lab considerations
1.3.1 Choosing your lab environment
1.3.2 Virtual lab considerations
1.3.3 Practicing on a live, production network
1.3.4 My recommendation for your lab environment
1.3.5 Cisco Internetwork Operating System versions
1.4 Online resources
1.5 A word on my recommendations
1.6 Being an immediately effective network administrator
2 What is a Cisco network?
2.1 The truth about routers and switches
2.2 MAC addresses
2.3 The Ethernet frame: a big envelope
2.3.1 When everybody talks, nobody listens
2.4 Broadcast domains
2.4.1 Closing the floodgates: the MAC address table
2.4.2 Breaking up the broadcast domain
2.4.3 Joining broadcast domains
2.4.4 Addressing devices across broadcast domains
2.5 Internet Protocol addresses
2.5.1 Where are you?
2.5.2 The IP vs. MAC dilemma
2.5.3 Address Resolution Protocol
2.6 Connecting broadcast domains using a router
2.6.1 Where are you? Where am I?
2.6.2 Understanding subnets
2.7 Traversing broadcast domains using a default gateway
2.8 Managing routers and switches
2.9 Hands-on lab
3 A crash course on Cisco’s Internetwork Operating System
3.1 What is IOS?
3.2 Logging into Cisco devices
3.3 The show command
3.3.1 Filtering output
3.4 Identifying the IOS version and package
3.4.1 Version numbers
3.4.2 Packages
3.5 Viewing the running configuration
3.6 Changing the running configuration
3.7 Saving the startup configuration
3.8 The no command
3.9 Commands in this chapter
3.10 Hands-on lab
4 Managing switch ports
4.1 Viewing port status
4.2 Enabling ports
4.2.1 The interface range command
4.3 Disabling ports
4.3.1 Finding unused interfaces
4.4 Changing the port speed and duplex
4.4.1 Speed
4.4.2 Duplex
4.4.3 Autonegotiation
4.4.4 Changing the port speed
4.4.5 Changing the duplex
4.5 Commands in this chapter
4.6 Hands-on lab
5 Securing ports by using the Port Security feature
5.1 The minimum Port Security configuration
5.1.1 Preventing MAC flood attacks
5.1.2 Violation modes
5.2 Testing Port Security
5.3 Handling device moves
5.3.1 Port Security never forgets!
5.3.2 Aging time
5.4 Preventing unauthorized devices
5.4.1 Making Port Security maximally secure
5.4.2 Sticky MAC addresses
5.4.3 Caveats about sticky MACs
5.5 Commands in this chapter
5.6 Hands-on lab
6 Managing virtual LANs (VLANs)
6.1 What is a VLAN?
6.2 Inventorying VLANs
6.2.1 The VLAN database
6.2.2 The default VLAN
6.2.3 How many VLANs should you create?
6.2.4 Planning a new VLAN
6.3 Creating VLANs
6.4 Assigning VLANs
6.4.1 Checking port configuration
6.4.2 Setting the access VLAN
6.4.3 Setting the access mode
6.5 Voice VLANs
6.6 Using your new VLANs
6.7 Commands in this chapter
6.8 Hands-on lab
7 Breaking the VLAN barrier by using switched virtual interfaces
7.1 Understanding the VLAN–subnet connection
7.2 Switches or routers?
7.2.1 Enabling IP routing
7.3 What are switched virtual interfaces?
7.3.1 Creating and configuring SVIs
7.4 Default gateways
7.4.1 Testing inter-VLAN connectivity
7.5 Commands in this chapter
7.6 Hands-on lab
8 IP address assignment by using Dynamic Host Configuration Protocol
8.1 To switch or not to switch?
8.2 Configuring a Cisco DHCP server
8.2.1 Scopes
8.2.2 Options
8.2.3 Lease time
8.2.4 Subnets and VLANs
8.3 Configuring a DHCP pool
8.4 Excluding addresses from assignment
8.5 Configuring devices to request DHCP addresses
8.6 Associating DHCP Pools with VLANs
8.7 Creating a second DHCP pool
8.8 Viewing DHCP leases
8.9 Using non-Cisco DHCP servers
8.9.1 Asking the switch for help using the ip helper-address command
8.10 Commands in this chapter
8.11 Hands-on lab
9 Securing the network by using IP access control lists
9.1 Blocking IP-to-IP traffic
9.1.1 Creating an access list
9.2 Applying an ACL to an interface
9.3 Blocking IP-to-subnet traffic
9.3.1 Wildcard masks
9.3.2 Replacing an ACL
9.3.3 Applying an access control list to a switched virtual interface
9.4 Blocking subnet-to-subnet traffic
9.5 Commands in this chapter
9.6 Hands-on lab
10 Connecting switches using trunk links
10.1 Connecting the new switch
10.2 Understanding VLAN trunk links
10.2.1 Configuring a trunk link
10.2.2 Configuring DTP to automatically negotiate a trunk
10.3 Configuring Switch2
10.3.1 Configuring VLANs on the new switch
10.4 Moving devices to the new switch
10.5 Changing the trunk encapsulation
10.6 Commands in this chapter
10.7 Hands-on lab
11 Automatically configuring VLANs using the VLAN Trunking Protocol
11.1 Two words of warning
11.2 Configuring Switch1 as a VTP server
11.3 Configuring Switch2 as a VTP client
11.4 Creating new VLANs on Switch1
11.5 Enabling VTP pruning
11.6 Commands in this chapter
11.7 Hands-on lab
12 Protecting against bridging loops by using the Spanning Tree Protocol
12.1 How Spanning Tree works
12.1.1 How Spanning Tree deals with link failures
12.2 Rapid Spanning Tree
12.3 PortFast
12.4 Commands in this chapter
12.5 Hands-on lab
13 Optimizing network performance by using port channels
13.1 Static or dynamic?
13.1.1 Static
13.1.2 Dynamic
13.2 Configuring a dynamic port channel using the Link Aggregation Control Protocol
13.3 Creating a static port channel
13.4 Load-balancing methods
13.5 Commands in this chapter
13.6 Hands-on lab
14 Making the network scalable by connecting routers and switches together
14.1 The router-on-a-stick configuration
14.2 Connecting Router1
14.3 Configuring subinterfaces
14.4 The IP routing table
14.5 Applying an ACL to a subinterface
14.6 Commands in this chapter
14.7 Hands-on lab
15 Manually directing traffic using the IP routing table
15.1 Connecting Router1 to Switch2
15.2 Configuring transit subnets
15.2.1 Assigning transit IP addresses directly to physical interfaces
15.2.2 Assigning transit IP addresses to subinterfaces and SVIs
15.3 Removing the trunk link between switches
15.4 Configuring default gateways
15.5 Creating a DHCP pool for the Executives subnet
15.6 Commands in this chapter
15.7 Hands-on lab
16 A dynamic routing protocols crash course
16.1 Understanding router IDs
16.1.1 Configuring loopback interfaces
16.2 Configuring EIGRP
16.2.1 Choosing the best path
16.2.2 Routing around failures
16.2.3 EIGRP recap
16.3 Open Shortest Path First
16.4 Commands used in this chapter
16.5 Hands-on lab
17 Tracking down devices
17.1 Device-tracking scenarios
17.2 Steps to tracking down a device
17.2.1 Get the IP address
17.2.2 Trace the device to the last hop
17.2.3 Get the MAC address
17.3 Example 1—Tracking down a network printer
17.3.1 Tracing to the last hop using traceroute
17.3.2 Cisco Discovery Protocol
17.3.3 Obtaining the MAC address of the device
17.3.4 Viewing the MAC address table
17.4 Example 2—Tracking down a server
17.4.1 Tracing to the last hop using traceroute
17.4.2 Obtaining the MAC address of the device
17.4.3 Viewing the MAC address table
17.5 Commands used in this chapter
17.6 Hands-on lab
18 Securing Cisco devices
18.1 Creating a privileged user account
18.1.1 Testing the account
18.2 Reconfiguring the VTY lines
18.2.1 Enabling SSH and disabling Telnet access
18.2.2 Restricting SSH access using access lists
18.3 Securing the console port
18.4 Commands used in this chapter
18.5 Hands-on lab
19 Facilitating troubleshooting using logging and debugging
19.1 Configuring the logging buffer
19.2 Debug commands
19.2.1 Debugging Port Security
19.2.2 Debugging DHCP
19.2.3 Debugging the VLAN Trunking Protocol
19.2.4 Debugging IP routing
19.3 Logging severity levels
19.4 Configuring syslogging
19.5 Commands used in this chapter
19.6 Hands-on lab
20 Recovering from disaster
20.1 Narrow the scope to a subset of devices
20.2 Reloading the device
20.2.1 Scheduling a reload
20.3 Deleting the startup configuration
20.4 Resetting the password
20.4.1 Resetting the password on a router
20.4.2 Resetting the password on a switch
20.5 Commands used in this chapter
21 Performance and health checklist
21.1 Is the CPU being overloaded?
21.2 What’s the system uptime?
21.3 Is there a damaged network cable or jack?
21.4 Are ping times unusually high or inconsistent?
21.5 Are routes flapping?
21.6 Commands in this chapter
21.7 Hands-on lab
22 Next steps
22.1 Certification resources
22.2 Cisco’s Virtual Internet Routing Lab
22.3 Troubleshooting end-user connectivity
22.4 Never the end
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