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Description

Perform a preliminary configuration of the wireless devices, consisting of the following steps:

Configure the device IDIDs.
Remove the svi1 interface.
Assign IP addresses to network interfaces, according to the scheme.
Add static entries to the routing table.
Disable switching.
Establish the wireless links.

BS1

Code Block

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Set the device ID
system prompt BS_1

Remove the svi1 interface
ifc svi1 destroy

Assign IP addresses
ifc eth0 10.10.10.1/24
ifc rf5.0 172.16.0.1/29
ifc lo0 192.168.0.1/32

Disable switching
switch stop

Establish wireless links
rf rf5.0 band 20
rf rf5.0 freq 5000

mint rf5.0 -name "BS_1"
mint rf5.0 -type master

CPE2

Code Block

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Set the device ID
system prompt CPE_2

Remove the svi1 interface
ifc svi1 destroy

Assign IP addresses
ifc eth0 10.10.20.2/24
ifc rf5.0 172.16.0.2/29
ifc lo0 192.168.0.2/32

Disable switching
switch stop

Establish the wireless link
mint rf5.0 -name "CPE_2"
mint rf5.0 -type slave
mint rf5.0 prof 1 -band 20 -freq 5000 -type slave

CPE3

Code Block

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Set the device ID
system prompt CPE_3

Remove the svi1 interface
ifc svi1 destroy

Assign IP addresses
ifc eth0 10.10.30.3/24
ifc rf5.0 172.16.0.3/29
ifc lo0 192.168.0.3/32

Add static routes
route add 192.168.5.0/28 10.10.30.1
route add 192.168.6.0/28 10.10.30.1

Disable switching
switch stop

Establish the wireless link
mint rf5.0 -name "CPE_3"
mint rf5.0 -type slave
mint rf5.0 prof 1 -band 20 -freq 5000 -type slave

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Description

Configure the OSPF protocol according to the scheme.

Step 1: start OSPF.

Step 2: set the router IDs. The identifiers will be equal to the IP addresses assigned to the loopback interface.

Step 3: define the interfaces where OSPF should be started. All the interfaces are connected to the backbone area according to the scheme. On the BS1 and CPE3 routers, set define the networks assigned to the device's interfaces that should take part in OSPF.

On the CPE2 router, set all the networks using only one entry 0.0.0.0/0. This entry includes all networks and enables the OSPF support on all router's interfaces; when a device's interface is connected to a new network, this network will be immediately announced via OSPF. This approach doesn't require additional OSPF configuration, but decreases the control over the announcements. In addition, this command advertises the address 127.0.0.1/32 that is assigned to the loopback interface and does not announce the address 192.168.0.2/32, therefore, this network must be additionally specified.

Step 4: perform the redistribution of the directly connected networks to the BS1 router and of the static routes on the CPE3 router.

Step 5: configure passive interfaces. The eth0 interface of CPE3 is connected to the outside external router R1, so no neighboring relation should be established on this interface. Network 10.10.30.0/24 associated with the eth0 interface must be announced via OSPF, so the eth0 interface must be set as passive.

BS1

Code Block

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Start OSPF
ospf start

Set the router-id
ospf
config
router
router-id 192.168.0.1

Start OSPF on the interfaces
ospf
config
router
network 172.16.0.0/29 area 0.0.0.0
network 192.168.0.1/32 area 0.0.0.0

ConnectedRedistribution of the connected routes redistribution
ospf
config
router
redistribute connected

CPE2

Code Block

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theme	Emacs

Start OSPF
ospf start

Set the router-id
ospf
config
router
router-id 192.168.0.2

Start OSPF on the interfaces
ospf
config
router
network 0.0.0.0/0 area 0.0.0.0
network 192.168.0.2/32 area 0.0.0.0

CPE3

Code Block

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theme	Emacs

Start OSPF
ospf start

Set the router-id
ospf
config
router
router-id 192.168.0.3

Start OSPF on the interfaces
ospf
config
router
network 10.10.30.0/24 area 0.0.0.0
 network 172.16.0.0/29 area 0.0.0.0
 network 192.168.0.3/32 area 0.0.0.0

StaticRedistribute the static routes redistribution
ospf
config
router
redistribute kernel

PassiveConfigure the interfacepassive configurationinterfaces
passive-interface eth0

Command output

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analysis

Neighbors list

Description

Analyze the neighbors. The routers are connected through the 172.16.0.0/29 network, which is a broadcast segment (using the MINT protocol), so:

CPE3 is elected as DR, its router-id being the highest.
CPE2 is elected as BDR, its router-id being the highest after CPE3.
BS1 is becomes DROther.
The routers have established Full relations.

BS1

Code Block

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OSPF> show neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface            RXmtL RqstL DBsmL
192.168.0.2       1   Full/Backup     00:00:38    172.16.0.2      rf5.0:172.16.0.1         0     0     0
192.168.0.3       1   Full/DR         00:00:38    172.16.0.3      rf5.0:172.16.0.1         0     0     0

CPE2

Code Block

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OSPF> show neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface            RXmtL RqstL DBsmL
192.168.0.1       1   Full/DROther    00:00:33    172.16.0.1      rf5.0:172.16.0.2         0     0     0
192.168.0.3       1   Full/DR         00:00:35    172.16.0.3      rf5.0:172.16.0.2         0     0     0

CPE3

Code Block

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theme	Emacs

OSPF> show neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface            RXmtL RqstL DBsmL
192.168.0.1       1   Full/DROther    00:00:31    172.16.0.1      rf5.0:172.16.0.3         0     0     0
192.168.0.2       1   Full/Backup     00:00:37    172.16.0.2      rf5.0:172.16.0.3         0     0     0

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Description

Analyze the LSDB. Since the scheme contains one area, the LSDB output on all the routers will be identical:

LSA type 1 (Router Link States): the LSDB contains three LSAs type 1, one from each of the area routers. Note that each LSA can contain a lot of information. For example, the LSA type 1 generated by CPE2 contains information about the neighbors, about the 172.16.0.0/29 and 10.10.20.0/24 networks and its own identifier.
LSA type 2 (Net Link States): CPE3 as DR has generated one LSA type 2.
LSA type 5 (AS External Link States): by default, one LSA type 5 is generated for each external route, therefore the LSDB contains three LSAs type 5, one for each external networksnetwork: the routes to the networks 192.168.5.0/28 and 192.168.6.0/28 were generated during the redistribution of the CPE3's static routes and the route to network 10.10.10.0/24 is generated by BS1 during the redistribution as a directly connected network.

BS1, CPE2, CPE3

Code Block

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OSPF> show database

       OSPF Router with ID (192.168.0.1)(192.168.0.1)

                Router Link States (Area 0.0.0.0)

Link ID         ADV Router      Age  Seq#       LS-Age Link count
192.168.0.1     192.168.0.1      202 0x80000008   7442 2
192.168.0.2     192.168.0.2      201 0x80000008   7405 3
192.168.0.3     192.168.0.3      204 0x8000000a   7407 3

                Net Link States (Area 0.0.0.0)

Link ID            ADV Router      Age  Seq#       LS-Age Routers
172.16.0.3/29      192.168.0.3      204 0x80000006   7407 3

                AS External Link States

Link ID         ADV Router      Age  Seq#       LS-Age Route
10.10.10.0      192.168.0.1      122 0x80000007   7442 E2 10.10.10.0/24      [0x0]
192.168.5.0     192.168.0.3      169 0x80000007   7407 E2 192.168.5.0/28     [0x0]
192.168.6.0     192.168.0.3      299 0x80000007   7407 E2 192.168.6.0/28     [0x0]

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Description

The routing tables of the wireless devices , contain entries for each subnet shown in the scheme. This means that the devices have successfully exchanged the routing information and added it to the FIB.

Note that the addresses of the loopback interfaces ' addresses do not depend on the link state, therefore they can be used to manage the devices in redundant networks.

BS1

Code Block

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BS_1#1> netstat -r
Routing tables
Destination        Gateway            Flags     Refs     Use  Interface
10.10.10.0/24      link#2             UC          0        0  eth0
10.10.20.0/24      172.16.0.2         UG3         0        0  rf5.0
10.10.30.0/24      172.16.0.3         UG3         0        0  rf5.0
127.0.0.1          127.0.0.1          UH          3      141  lo0
172.16.0.0/29      link#3             UC          0        0  rf5.0
192.168.0.1        192.168.0.1        UH          0        0  lo0
192.168.0.2        172.16.0.2         UGH3        0        0  rf5.0
192.168.0.3        172.16.0.3         UGH3        0        0  rf5.0
192.168.5.0/28     172.16.0.3         UG3         0        0  rf5.0
192.168.6.0/28     172.16.0.3         UG3         0        0  rf5.0
224.0.0.0/8        127.0.0.1          UGS         1     1561  lo0

CPE2

Code Block

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AS_2#2> netstat -r
Routing tables
Destination        Gateway            Flags     Refs     Use  Interface
10.10.10.0/24      172.16.0.1         UG3         0        0  rf5.0
10.10.20.0/24      link#2             UC          0        0  eth0
10.10.30.0/24      172.16.0.3         UG3         0        0  rf5.0
127.0.0.1          127.0.0.1          UH          3       50  lo0
172.16.0.0/29      link#3             UC          0        0  rf5.0
192.168.0.1        172.16.0.1         UGH3        0        0  rf5.0
192.168.0.2        192.168.0.2        UH          0        0  lo0
192.168.0.3        172.16.0.3         UGH3        0        0  rf5.0
192.168.5.0/28     172.16.0.3         UG3         0        0  rf5.0
192.168.6.0/28     172.16.0.3         UG3         0        0  rf5.0
224.0.0.0/8        127.0.0.1          UGS         1     2037  lo0

CPE3

Code Block

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AS_3#1> netstat -r
Routing tables
Destination        Gateway            Flags     Refs     Use  Interface
10.10.10.0/24      172.16.0.1         UG3         0        0  rf5.0
10.10.20.0/24      172.16.0.2         UG3         0        0  rf5.0
10.10.30.0/24      link#2             UC          0        0  eth0
127.0.0.1          127.0.0.1          UH          3      155  lo0
172.16.0.0/29      link#3             UC          0        0  rf5.0
192.168.0.1        172.16.0.1         UGH3        0        0  rf5.0
192.168.0.2        172.16.0.2         UGH3        0        0  rf5.0
192.168.0.3        192.168.0.3        UH          0        0  lo0
192.168.5.0/28     10.10.30.1         UGS         0        0  eth0
192.168.6.0/28     10.10.30.1         UGS         0        0  eth0
224.0.0.0/8        127.0.0.1          UGS         1     1745  lo0

...

Description

Let's configure the OSPF protocol according to the scheme.

Step 1: start OSPF.

Step 2: configure the router IDs. The identifiers will be equal to the IP addresses assigned to the loopback interface.

Step 3: define the interfaces where OSPF should be started. All the interfaces are connected to the backbone area according to the scheme.

Step 4: define the area types: area 3 - NSSA, area 4 - Stub. Note that the area type must be configured on all the routers connected to that area, otherwise they will not establish neighboring relations.

Step 5: perform the redistribution of the directly connected networks on the BS1 router and pf the static routes on the CPE3 router.

Step 6: configure passive interfaces.

BS1

Code Block

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theme	Emacs

Start OSPF
ospf start

Set the router-id
ospf
config
router
router-id 192.168.0.1

Start OSPF on the interfaces
ospf
config
router
network 172.16.0.0/30 area 0.0.0.0
network 172.16.3.0/30 area 0.0.0.3
network 172.16.4.0/30 area 0.0.0.4
network 192.168.0.1/32 area 0.0.0.0

Set the area types
ospf
config
router
area 0.0.0.3 nssa
area 0.0.0.4 stub

Redistribute the connected routes
ospf
config
router
redistribute connected

CPE2

Code Block

language	text
theme	Emacs

Start OSPF
ospf start

Set the router-id
ospf
config
router
router-id 192.168.0.2

Start OSPF on the interfaces
ospf
config
router
network 10.10.20.0/24 area 0.0.0.0
network 172.16.0.0/30 area 0.0.0.0
network 192.168.0.2/32 area 0.0.0.0

CPE3

Code Block

language	text
theme	Emacs

Start OSPF
ospf start

Set the router-id
ospf
config
router
router-id 192.168.0.3

Start OSPF on the interfaces
ospf
config
router
network 10.10.30.0/24 area 0.0.0.3
network 172.16.3.0/30 area 0.0.0.3
network 192.168.0.3/32 area 0.0.0.3

Set the area types
ospf
config
router
area 0.0.0.3 nssa

Redistribute the static routes
ospf
config
router
redistribute kernel

Set the passive interfaces
passive-interface eth0

CPE4

Code Block

language	text
theme	Emacs

Start OSPF
ospf start

Set the router-id
ospf
config
router
router-id 192.168.0.4

Start OSPF on the interfaces
ospf
config
router
network 10.10.40.0/24 area 0.0.0.4
network 172.16.4.0/30 area 0.0.0.4
network 192.168.0.4/32 area 0.0.0.4

Set the area types
ospf
config
router
area 0.0.0.4 stub

Redistribute the static routes
ospf
config
router
redistribute kernel

Command output analysis

Neighbors list

Description

Let's analyze the neighbors list. The routers are connected by the MINT network, but each wireless connection has its own subnet.

Routers CPE2, CPE3 and CPE4 have established a neighboring relation only with BS1, which means that a neighboring relation can be established only within one area.

Routers CPE2, CPE3 and CPE4 are selected as DR, BS1 - BDR, as BS1's router ID is the lowest.

BS1

Code Block

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OSPF> show neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface            RXmtL RqstL DBsmL
192.168.0.2       1   Full/DR         00:00:32    172.16.0.2      rf5.0:172.16.0.1         0     0     0
192.168.0.3       1   Full/DR         00:00:34    172.16.3.2      rf5.0:172.16.3.1         0     0     0
192.168.0.4       1   Full/DR         00:00:32    172.16.4.2      rf5.0:172.16.4.1         0     0     0

CPE2

Code Block

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OSPF> show neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface            RXmtL RqstL DBsmL
192.168.0.1       1   Full/Backup     00:00:32    172.16.0.1      rf5.0:172.16.0.2         0     0     0

CPE3

Code Block

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theme	Emacs

OSPF> show neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface            RXmtL RqstL DBsmL
192.168.0.1       1   Full/Backup     00:00:31    172.16.3.1      rf5.0:172.16.3.2         0     0     0

CPE4

Code Block

language	text
theme	Emacs

OSPF> show neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface            RXmtL RqstL DBsmL
192.168.0.1       1   Full/Backup     00:00:37    172.16.4.1      rf5.0:172.16.4.2         0     0     0

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Versions Compared

Old Version 13

New Version 14

Key

Command output

analysis

Neighbors list

Command output analysis

Neighbors list