ICND1 | Interconnecting Cisco Networking Devices 1

RIPv2 is one of the easiest routing protocols to configure, making it a good choice for small networks. However, RIPv2 still has limitations. RIPv2 has a route metric that is based only on hop count and is limited to 15 hops. To enter the router configuration mode for RIP, enter the router rip command at the global configuration prompt. The prompt changes to the router configuration prompt. To enable RIP routing for a network, use the network command in the router configuration mode. The network command assigns a major network number to which the router is directly connected. The RIP routing process associates interface addresses with the advertised network number and will begin RIP packet processing on the specified interfaces.

The network command enables RIP on all interfaces that belong to a specific network and advertises the specified networks. The networks 176.16.1.0 and 176.16.2.0 need to be advertised. The 176.16.2.0 is the local network associated with the 172.16.2.1 IP address on the S0/0/1 interface.
RIPv2 is one of the easiest routing protocols to configure, making it a good choice for small networks. However, RIPv2 still has limitations. RIPv2 has a route metric that is based only on hop count and is limited to 15 hops. To enter the router configuration mode for RIP, enter the router rip command at the global configuration prompt. The prompt changes to the router configuration prompt. To enable RIP routing for a network, use the network command in the router configuration mode. The network command assigns a major network number to which the router is directly connected. The RIP routing process associates interface addresses with the advertised network number and will begin RIP packet processing on the specified interfaces.

The network command enables RIP on all interfaces that belong to a specific network and advertises the specified networks. The networks 176.16.1.0 and 176.16.2.0 need to be advertised. The 176.16.2.0 is the local network associated with the 172.16.2.1 IP address on the S0/0/1 interface.
RIPv2 is one of the easiest routing protocols to configure, making it a good choice for small networks. However, RIPv2 still has limitations. RIPv2 has a route metric that is based only on hop count and is limited to 15 hops. To enter the router configuration mode for RIP, enter the router rip command at the global configuration prompt. The prompt changes to the router configuration prompt. To enable RIP routing for a network, use the network command in the router configuration mode. The network command assigns a major network number to which the router is directly connected. The RIP routing process associates interface addresses with the advertised network number and will begin RIP packet processing on the specified interfaces.

The network command enables RIP on all interfaces that belong to a specific network and advertises the specified networks. The networks 176.16.1.0 and 176.16.2.0 need to be advertised. The 176.16.2.0 is the local network associated with the 172.16.2.1 IP address on the S0/0/1 interface.

The service password-encryption command is used to encrypt all user account passwords in the user account database. Passwords that are displayed or set after you configure the service password-encryption command will be encrypted. Service password encryption uses type-7 encryption, which is not very secure. Several tools and web pages are available to convert an encrypted password into a plain text string.

The enable secret global configuration command will specify the password to use when accessing privileged EXEC mode. The enable password global configuration command will specify the unencrypted password to use when accessing privileged EXEC mode. A configured enable secret password will take precedence over a configured enable password. The username global configuration command is used to create a local user account database, which is used to provide username-based authentication when enabled on a line.
The service password-encryption command is used to encrypt all user account passwords in the user account database. Passwords that are displayed or set after you configure the service password-encryption command will be encrypted. Service password encryption uses type-7 encryption, which is not very secure. Several tools and web pages are available to convert an encrypted password into a plain text string.

The enable secret global configuration command will specify the password to use when accessing privileged EXEC mode. The enable password global configuration command will specify the unencrypted password to use when accessing privileged EXEC mode. A configured enable secret password will take precedence over a configured enable password. The username global configuration command is used to create a local user account database, which is used to provide username-based authentication when enabled on a line.
The service password-encryption command is used to encrypt all user account passwords in the user account database. Passwords that are displayed or set after you configure the service password-encryption command will be encrypted. Service password encryption uses type-7 encryption, which is not very secure. Several tools and web pages are available to convert an encrypted password into a plain text string.

The enable secret global configuration command will specify the password to use when accessing privileged EXEC mode. The enable password global configuration command will specify the unencrypted password to use when accessing privileged EXEC mode. A configured enable secret password will take precedence over a configured enable password. The username global configuration command is used to create a local user account database, which is used to provide username-based authentication when enabled on a line.

The show interfaces command displays the status and statistical information for the network interfaces of the switch. The resulting output varies, depending on the network for which a particular interface has been configured.

The show interfaces command is used to determine if a port is error disabled. This status occurs if there is a cabling/NIC problem or a duplex mismatch. If a port is error disabled, the status will show as err-disabled.
The show interfaces command displays the status and statistical information for the network interfaces of the switch. The resulting output varies, depending on the network for which a particular interface has been configured.

The show interfaces command is used to determine if a port is error disabled. This status occurs if there is a cabling/NIC problem or a duplex mismatch. If a port is error disabled, the status will show as err-disabled.
The show interfaces command displays the status and statistical information for the network interfaces of the switch. The resulting output varies, depending on the network for which a particular interface has been configured.

The show interfaces command is used to determine if a port is error disabled. This status occurs if there is a cabling/NIC problem or a duplex mismatch. If a port is error disabled, the status will show as err-disabled.

A firewall typically establishes a barrier between a trusted, secure internal network and another outside network, such as the Internet, that is assumed not to be secure or trusted. These devices are network security systems that monitor and control the incoming and outgoing network traffic based on predetermined security rules. Other device such as routers, access points, and WLAN controllers are not considered security devices that monitor traffic from inside networks to outside networks.
A firewall typically establishes a barrier between a trusted, secure internal network and another outside network, such as the Internet, that is assumed not to be secure or trusted. These devices are network security systems that monitor and control the incoming and outgoing network traffic based on predetermined security rules. Other device such as routers, access points, and WLAN controllers are not considered security devices that monitor traffic from inside networks to outside networks.
A firewall typically establishes a barrier between a trusted, secure internal network and another outside network, such as the Internet, that is assumed not to be secure or trusted. These devices are network security systems that monitor and control the incoming and outgoing network traffic based on predetermined security rules. Other device such as routers, access points, and WLAN controllers are not considered security devices that monitor traffic from inside networks to outside networks.

The show ip nat statistics command is used to verify if any translations have ever taken place, and to identify the interfaces between which the translation should be occurring. The following is an example of the output generated from issuing the show ip nat statistics command:

|f Helvetica RouterA# show ip nat statistics
|f Helvetica |w |w |w |w |w |w |w |w |w |w Total active translations: 3 (0 static, 3 dynamic; 0 extended)
|f Helvetica |w |w |w |w |w |w |w |w |w |w Outside interfaces:
|f Helvetica |w |w |w |w |w |w |w |w |w |w Serial0
|f Helvetica |w |w |w |w |w |w |w |w |w |w Inside interfaces:
|f Helvetica |w |w |w |w |w |w |w |w |w |w Ethernet0
|f Helvetica |w |w |w |w |w |w |w |w |w |w Hits: 103 |w Misses: 3 |w

From this output, you can determine that there are three active translations and that the software has successfully looked up 103 entries in the translations table. If there were no hits, then no translations would have taken place. The other commands do not provide past translation activity.
The show ip nat statistics command is used to verify if any translations have ever taken place, and to identify the interfaces between which the translation should be occurring. The following is an example of the output generated from issuing the show ip nat statistics command:

|f Helvetica RouterA# show ip nat statistics
|f Helvetica |w |w |w |w |w |w |w |w |w |w Total active translations: 3 (0 static, 3 dynamic; 0 extended)
|f Helvetica |w |w |w |w |w |w |w |w |w |w Outside interfaces:
|f Helvetica |w |w |w |w |w |w |w |w |w |w Serial0
|f Helvetica |w |w |w |w |w |w |w |w |w |w Inside interfaces:
|f Helvetica |w |w |w |w |w |w |w |w |w |w Ethernet0
|f Helvetica |w |w |w |w |w |w |w |w |w |w Hits: 103 |w Misses: 3 |w

From this output, you can determine that there are three active translations and that the software has successfully looked up 103 entries in the translations table. If there were no hits, then no translations would have taken place. The other commands do not provide past translation activity.
The show ip nat statistics command is used to verify if any translations have ever taken place, and to identify the interfaces between which the translation should be occurring. The following is an example of the output generated from issuing the show ip nat statistics command:

|f Helvetica RouterA# show ip nat statistics
|f Helvetica |w |w |w |w |w |w |w |w |w |w Total active translations: 3 (0 static, 3 dynamic; 0 extended)
|f Helvetica |w |w |w |w |w |w |w |w |w |w Outside interfaces:
|f Helvetica |w |w |w |w |w |w |w |w |w |w Serial0
|f Helvetica |w |w |w |w |w |w |w |w |w |w Inside interfaces:
|f Helvetica |w |w |w |w |w |w |w |w |w |w Ethernet0
|f Helvetica |w |w |w |w |w |w |w |w |w |w Hits: 103 |w Misses: 3 |w

From this output, you can determine that there are three active translations and that the software has successfully looked up 103 entries in the translations table. If there were no hits, then no translations would have taken place. The other commands do not provide past translation activity.

A routing table contains a list of all networks that are known to the router and information about how to reach those networks. Each line, or entry, of the routing table lists a destination network and the interface or next-hop address by which that destination network can be reached. To display the routing table on a Cisco router, you can use the show ip route command. OSPF has an administrative distance of 110. You can quickly tell which protocol the router is using on the left most column on the routing table by reading the letter. For instance, OSPF will have a capital O.
A routing table contains a list of all networks that are known to the router and information about how to reach those networks. Each line, or entry, of the routing table lists a destination network and the interface or next-hop address by which that destination network can be reached. To display the routing table on a Cisco router, you can use the show ip route command. OSPF has an administrative distance of 110. You can quickly tell which protocol the router is using on the left most column on the routing table by reading the letter. For instance, OSPF will have a capital O.
A routing table contains a list of all networks that are known to the router and information about how to reach those networks. Each line, or entry, of the routing table lists a destination network and the interface or next-hop address by which that destination network can be reached. To display the routing table on a Cisco router, you can use the show ip route command. OSPF has an administrative distance of 110. You can quickly tell which protocol the router is using on the left most column on the routing table by reading the letter. For instance, OSPF will have a capital O.

The logging trap command will allow an administrator to restrict the severity of messages that are logged to the specified syslog servers when followed by a number, such as 7. For example, the command logging trap 0 will limit the level of system logging messages sent to a syslog server to emergency messages only.

The command logging trap 7 will allow debugging messages and the other seven levels of messages, from 0 to 6, to be sent to a syslog server. Therefore, this command will not limit the level of system logging messages sent to a syslog server to emergency messages only.

The logging timestamp command determines whether the date and time of the message generation should also be included in the syslog message.

The logging console command will allow an administrator to restrict the severity of messages that are logged to the console when followed by a number, such as 0. For example, the command logging console 0 will limit the types of messages logged on the console to emergency only.
The logging trap command will allow an administrator to restrict the severity of messages that are logged to the specified syslog servers when followed by a number, such as 7. For example, the command logging trap 0 will limit the level of system logging messages sent to a syslog server to emergency messages only.

The command logging trap 7 will allow debugging messages and the other seven levels of messages, from 0 to 6, to be sent to a syslog server. Therefore, this command will not limit the level of system logging messages sent to a syslog server to emergency messages only.

The logging timestamp command determines whether the date and time of the message generation should also be included in the syslog message.

The logging console command will allow an administrator to restrict the severity of messages that are logged to the console when followed by a number, such as 0. For example, the command logging console 0 will limit the types of messages logged on the console to emergency only.
The logging trap command will allow an administrator to restrict the severity of messages that are logged to the specified syslog servers when followed by a number, such as 7. For example, the command logging trap 0 will limit the level of system logging messages sent to a syslog server to emergency messages only.

The command logging trap 7 will allow debugging messages and the other seven levels of messages, from 0 to 6, to be sent to a syslog server. Therefore, this command will not limit the level of system logging messages sent to a syslog server to emergency messages only.

The logging timestamp command determines whether the date and time of the message generation should also be included in the syslog message.

The logging console command will allow an administrator to restrict the severity of messages that are logged to the console when followed by a number, such as 0. For example, the command logging console 0 will limit the types of messages logged on the console to emergency only.

During a password recovery, the router needs to be configured to ignore the startup configuration file as it includes the forgotten password. The 0x2142 configuration register value will instruct the router to bypass NVRAM; therefore, ignoring the startup configuration file. While performing a password recover, the configuration register value is changed in ROM monitor.

The 0x2100 configuration register value will not instruct the router to bypass the startup configuration file stored in NVRAM. This configuration register value will boot the router into ROM monitor at the next power cycle or reload.

The 0x2141 configuration register value will instruct the router to bypass the startup configuration file stored in NVRAM; however, it will also instruct the router to attempt to load the Cisco IOS Software image from ROM.

The 0x2102 configuration register value will instruct the router to attempt to load the Cisco IOS Software image from flash memory and to load the startup configuration file from NVRAM.
During a password recovery, the router needs to be configured to ignore the startup configuration file as it includes the forgotten password. The 0x2142 configuration register value will instruct the router to bypass NVRAM; therefore, ignoring the startup configuration file. While performing a password recover, the configuration register value is changed in ROM monitor.

The 0x2100 configuration register value will not instruct the router to bypass the startup configuration file stored in NVRAM. This configuration register value will boot the router into ROM monitor at the next power cycle or reload.

The 0x2141 configuration register value will instruct the router to bypass the startup configuration file stored in NVRAM; however, it will also instruct the router to attempt to load the Cisco IOS Software image from ROM.

The 0x2102 configuration register value will instruct the router to attempt to load the Cisco IOS Software image from flash memory and to load the startup configuration file from NVRAM.
During a password recovery, the router needs to be configured to ignore the startup configuration file as it includes the forgotten password. The 0x2142 configuration register value will instruct the router to bypass NVRAM; therefore, ignoring the startup configuration file. While performing a password recover, the configuration register value is changed in ROM monitor.

The 0x2100 configuration register value will not instruct the router to bypass the startup configuration file stored in NVRAM. This configuration register value will boot the router into ROM monitor at the next power cycle or reload.

The 0x2141 configuration register value will instruct the router to bypass the startup configuration file stored in NVRAM; however, it will also instruct the router to attempt to load the Cisco IOS Software image from ROM.

The 0x2102 configuration register value will instruct the router to attempt to load the Cisco IOS Software image from flash memory and to load the startup configuration file from NVRAM.

If severity level 2 is configured, only emergency (severity 0), alert (severity 1), and critical (severity 2) messages will be displayed. Cisco syslog messages fall into one of eight levels. The lower the level number, the higher the severity level. The configured severity level indicates the maximum level of severity for which the router should generate syslog messages.

If severity level 5 is configured, emergency (severity 0), alert (severity 1), critical (severity 2), error (severity 3), warning (severity 4), and notification (severity 5) messages will be displayed. If severity level 4 is configured, emergency (severity 0), to warning (severity 4) messages will be displayed. If severity level 3 is configured, emergency (severity 0) to error (severity 3) messages will be displayed.
If severity level 2 is configured, only emergency (severity 0), alert (severity 1), and critical (severity 2) messages will be displayed. Cisco syslog messages fall into one of eight levels. The lower the level number, the higher the severity level. The configured severity level indicates the maximum level of severity for which the router should generate syslog messages.

If severity level 5 is configured, emergency (severity 0), alert (severity 1), critical (severity 2), error (severity 3), warning (severity 4), and notification (severity 5) messages will be displayed. If severity level 4 is configured, emergency (severity 0), to warning (severity 4) messages will be displayed. If severity level 3 is configured, emergency (severity 0) to error (severity 3) messages will be displayed.
If severity level 2 is configured, only emergency (severity 0), alert (severity 1), and critical (severity 2) messages will be displayed. Cisco syslog messages fall into one of eight levels. The lower the level number, the higher the severity level. The configured severity level indicates the maximum level of severity for which the router should generate syslog messages.

If severity level 5 is configured, emergency (severity 0), alert (severity 1), critical (severity 2), error (severity 3), warning (severity 4), and notification (severity 5) messages will be displayed. If severity level 4 is configured, emergency (severity 0), to warning (severity 4) messages will be displayed. If severity level 3 is configured, emergency (severity 0) to error (severity 3) messages will be displayed.

When the IP packet travels across the network topology as shown in the exhibit, it will be manipulated by the devices and changed based on the interfaces information. The layer 3 header is made up of the source and destination IP addresses, which do not change. However the source and destination MAC addresses in the layer 2 header will change.

When a packet leaves Router B, the source MAC address will be that of Fa0/0. Its source and destination IP address will be 10.3.3.2 and 10.2.2.2 respectively.

A MAC address is an Ethernet technology, therefore a serial port would not have a MAC address.
When the IP packet travels across the network topology as shown in the exhibit, it will be manipulated by the devices and changed based on the interfaces information. The layer 3 header is made up of the source and destination IP addresses, which do not change. However the source and destination MAC addresses in the layer 2 header will change.

When a packet leaves Router B, the source MAC address will be that of Fa0/0. Its source and destination IP address will be 10.3.3.2 and 10.2.2.2 respectively.

A MAC address is an Ethernet technology, therefore a serial port would not have a MAC address.
When the IP packet travels across the network topology as shown in the exhibit, it will be manipulated by the devices and changed based on the interfaces information. The layer 3 header is made up of the source and destination IP addresses, which do not change. However the source and destination MAC addresses in the layer 2 header will change.

When a packet leaves Router B, the source MAC address will be that of Fa0/0. Its source and destination IP address will be 10.3.3.2 and 10.2.2.2 respectively.

A MAC address is an Ethernet technology, therefore a serial port would not have a MAC address.

Traceroute is a utility that allows observation of the path between two hosts. This can be performed by entering traceroute 192.168.1.1 at the privilege EXEC command prompt of R1. The trace generates a list of hops that are successfully reached along the path. If the data reaches the destination, the trace lists the interface on every router in the path. If the data fails at some hop along the way, the address of the last router that responded to the trace is known. This address is an indication of where the problem or security restrictions reside.

The ping command is used to verify connectivity between two hosts. However, it will not display the path taken between the two hosts. The tracert command, like the traceroute command, is used to verify the route taken between two hosts. However, this would be a Windows command, not a Cisco IOS command.
Traceroute is a utility that allows observation of the path between two hosts. This can be performed by entering traceroute 192.168.1.1 at the privilege EXEC command prompt of R1. The trace generates a list of hops that are successfully reached along the path. If the data reaches the destination, the trace lists the interface on every router in the path. If the data fails at some hop along the way, the address of the last router that responded to the trace is known. This address is an indication of where the problem or security restrictions reside.

The ping command is used to verify connectivity between two hosts. However, it will not display the path taken between the two hosts. The tracert command, like the traceroute command, is used to verify the route taken between two hosts. However, this would be a Windows command, not a Cisco IOS command.
Traceroute is a utility that allows observation of the path between two hosts. This can be performed by entering traceroute 192.168.1.1 at the privilege EXEC command prompt of R1. The trace generates a list of hops that are successfully reached along the path. If the data reaches the destination, the trace lists the interface on every router in the path. If the data fails at some hop along the way, the address of the last router that responded to the trace is known. This address is an indication of where the problem or security restrictions reside.

The ping command is used to verify connectivity between two hosts. However, it will not display the path taken between the two hosts. The tracert command, like the traceroute command, is used to verify the route taken between two hosts. However, this would be a Windows command, not a Cisco IOS command.

You use the clock summer-time command to allow a Cisco device to automatically switch to summer time. Summer time is also known as daylight saving time.

To disable automatic switching to summer time, you can use the following command:

no clock summer-time

By default, summer time is disabled. This command is performed in the Global configuration mode.

The clock timezone command allows you to set the time zone for the Cisco device. The clock read-calendar command configures the software clock to set its date and time by the hardware clock setting. The clock update-calendar command performs a one-time update of the hardware clock from the software clock.

A floating static route is a route that has a higher administrative distance then the current route in a routers routing table. It is similar to a static route, but the administrative distances would be one higher than the existing route in the routers routing table. For example, if the router has a route that uses OSPF, which has an administrative distance of 110, the static floating route would have an administrative distance of 111. If the OSPF route fails, the floating route will kick in. A static route would have an administrative distance of 1.
A floating static route is a route that has a higher administrative distance then the current route in a routers routing table. It is similar to a static route, but the administrative distances would be one higher than the existing route in the routers routing table. For example, if the router has a route that uses OSPF, which has an administrative distance of 110, the static floating route would have an administrative distance of 111. If the OSPF route fails, the floating route will kick in. A static route would have an administrative distance of 1.
A floating static route is a route that has a higher administrative distance then the current route in a routers routing table. It is similar to a static route, but the administrative distances would be one higher than the existing route in the routers routing table. For example, if the router has a route that uses OSPF, which has an administrative distance of 110, the static floating route would have an administrative distance of 111. If the OSPF route fails, the floating route will kick in. A static route would have an administrative distance of 1.

Passwords that are displayed or set after you configure the service password-encryption command will be encrypted. Service password encryption uses type-7 encryption, which is not very secure. This can be determined from the number seven after the word "password" in the syntax. Several tools and web pages available can convert an encrypted password into a plain text string.

The password is encrypted and 106D000A0618 is not the actual password. Since a username is present in the show run output, the enable secret command has not been used. This command is used to configure a password only, not a username and a password. The secret command applies a strong MD5 hash to passwords, and it is considered a type-5 encryption. This configuration is identified by the number 5 after the word "secret" in the command output.
Passwords that are displayed or set after you configure the service password-encryption command will be encrypted. Service password encryption uses type-7 encryption, which is not very secure. This can be determined from the number seven after the word "password" in the syntax. Several tools and web pages available can convert an encrypted password into a plain text string.

The password is encrypted and 106D000A0618 is not the actual password. Since a username is present in the show run output, the enable secret command has not been used. This command is used to configure a password only, not a username and a password. The secret command applies a strong MD5 hash to passwords, and it is considered a type-5 encryption. This configuration is identified by the number 5 after the word "secret" in the command output.
Passwords that are displayed or set after you configure the service password-encryption command will be encrypted. Service password encryption uses type-7 encryption, which is not very secure. This can be determined from the number seven after the word "password" in the syntax. Several tools and web pages available can convert an encrypted password into a plain text string.

The password is encrypted and 106D000A0618 is not the actual password. Since a username is present in the show run output, the enable secret command has not been used. This command is used to configure a password only, not a username and a password. The secret command applies a strong MD5 hash to passwords, and it is considered a type-5 encryption. This configuration is identified by the number 5 after the word "secret" in the command output.

A default route is an optional entry that is used when no explicit path to a destination is found in the routing table. This is also referred to as the gateway of last resort. The default route can be manually inserted or it can be populated from a dynamic routing protocol. The syntax for a default static route is the same as other static routes, except that the network address is 0.0.0.0 and the subnet mask is 0.0.0.0. Additionally, a default static route is identified by the letter "S" with an asterisk (*) for the code output. This makes default static routes easy to identify. A directly connected network is identified by the “C” code.
A default route is an optional entry that is used when no explicit path to a destination is found in the routing table. This is also referred to as the gateway of last resort. The default route can be manually inserted or it can be populated from a dynamic routing protocol. The syntax for a default static route is the same as other static routes, except that the network address is 0.0.0.0 and the subnet mask is 0.0.0.0. Additionally, a default static route is identified by the letter "S" with an asterisk (*) for the code output. This makes default static routes easy to identify. A directly connected network is identified by the “C” code.
A default route is an optional entry that is used when no explicit path to a destination is found in the routing table. This is also referred to as the gateway of last resort. The default route can be manually inserted or it can be populated from a dynamic routing protocol. The syntax for a default static route is the same as other static routes, except that the network address is 0.0.0.0 and the subnet mask is 0.0.0.0. Additionally, a default static route is identified by the letter "S" with an asterisk (*) for the code output. This makes default static routes easy to identify. A directly connected network is identified by the “C” code.