I am really a sys admin pretending to be a network engineer and need clarification on ospf redistribution and route summarization.

Our topology:

Layer3 switches (6509s and 4506s) with WAN connection to AT&T MPLS cloud to other sites. We are running OSPF at each site and redistributing tagged routes to AT&T’s router for redistribution across their BGP back into our OSPF at each site.

Example of our routing config at each site:

router ospf 1

router-id 10.152.200.2

log-adjacency-changes

auto-cost reference-bandwidth 10000

passive-interface default

no passive-interface Vlan300

no passive-interface Vlan600

network 10.144.0.0 0.15.255.255 area 0

network 10.250.152.0 0.0.0.255 area 0

route-map STATIC-OSPF permit 10

match tag 30

One of our sites has a ton of subnets that are being advertised and I need to summarize the routes being redistributed to AT&T’s WAN router.

A

#sho ip route connected

10.0.0.0/8 is variably subnetted, 102 subnets, 5 masks

C 10.152.212.0/24 is directly connected, Vlan212

C 10.152.200.0/22 is directly connected, Vlan200

C 10.152.205.0/24 is directly connected, Vlan205

C 10.250.152.0/24 is directly connected, Vlan250

C 10.152.250.0/24 is directly connected, Vlan600

C 10.152.18.0/24 is directly connected, Vlan18

C 10.152.19.0/24 is directly connected, Vlan19

C 10.152.16.0/24 is directly connected, Vlan16

C 10.152.17.0/24 is directly connected, Vlan17

C 10.152.22.0/24 is directly connected, Vlan22

C 10.152.23.0/24 is directly connected, Vlan23

C 10.152.20.0/24 is directly connected, Vlan20

C 10.152.21.0/24 is directly connected, Vlan21

C 10.152.26.0/24 is directly connected, Vlan26

C 10.152.27.0/24 is directly connected, Vlan27

C 10.152.24.0/24 is directly connected, Vlan24

C 10.152.25.0/24 is directly connected, Vlan25

C 10.152.30.0/24 is directly connected, Vlan30

C 10.152.31.0/24 is directly connected, Vlan31

C 10.152.28.0/24 is directly connected, Vlan28

C 10.152.29.0/24 is directly connected, Vlan29

C 10.152.255.253/32 is directly connected, Loopback100

C 10.152.0.0/24 is directly connected, Vlan300

C 10.152.255.254/32 is directly connected, Loopback101

C 10.152.6.0/24 is directly connected, Vlan6

C 10.152.7.0/24 is directly connected, Vlan7

C 10.152.5.0/24 is directly connected, Vlan5

C 10.152.10.0/24 is directly connected, Vlan10

C 10.152.11.0/24 is directly connected, Vlan11

C 10.152.8.0/24 is directly connected, Vlan8

C 10.152.9.0/24 is directly connected, Vlan9

C 10.152.14.0/24 is directly connected, Vlan14

C 10.152.15.0/24 is directly connected, Vlan15

C 10.152.12.0/24 is directly connected, Vlan12

C 10.152.13.0/24 is directly connected, Vlan13

C 10.152.50.0/24 is directly connected, Vlan50

C 10.152.51.0/24 is directly connected, Vlan51

C 10.152.48.0/24 is directly connected, Vlan48

C 10.152.49.0/24 is directly connected, Vlan49

C 10.152.54.0/24 is directly connected, Vlan54

C 10.152.55.0/24 is directly connected, Vlan55

C 10.152.52.0/24 is directly connected, Vlan52

C 10.152.53.0/24 is directly connected, Vlan53

C 10.152.58.0/24 is directly connected, Vlan58

C 10.152.59.0/24 is directly connected, Vlan59

C 10.152.56.0/24 is directly connected, Vlan56

C 10.152.57.0/24 is directly connected, Vlan57

C 10.152.34.0/24 is directly connected, Vlan34

C 10.152.35.0/24 is directly connected, Vlan35

C 10.152.32.0/24 is directly connected, Vlan32

C 10.152.33.0/24 is directly connected, Vlan33

C 10.152.38.0/24 is directly connected, Vlan38

C 10.152.39.0/24 is directly connected, Vlan39

C 10.152.36.0/24 is directly connected, Vlan36

C 10.152.37.0/24 is directly connected, Vlan37

C 10.152.42.0/24 is directly connected, Vlan42

C 10.152.43.0/24 is directly connected, Vlan43

C 10.152.40.0/24 is directly connected, Vlan40

C 10.152.41.0/24 is directly connected, Vlan41

C 10.152.46.0/24 is directly connected, Vlan46

C 10.152.47.0/24 is directly connected, Vlan47

C 10.152.44.0/24 is directly connected, Vlan44

C 10.152.208.253/32 is directly connected, Loopback0

C 10.152.45.0/24 is directly connected, Vlan45

C 10.152.82.0/24 is directly connected, Vlan82

C 10.152.80.0/24 is directly connected, Vlan80

C 10.152.81.0/24 is directly connected, Vlan81

C 10.152.102.0/24 is directly connected, Vlan102

C 10.152.100.0/24 is directly connected, Vlan100

C 10.152.101.0/24 is directly connected, Vlan101

I’m trying to figure out which command I need to use: the

Should I add

Router ospf 1

Area 0 range 10.144.0.0 255.240.0.0

OR

Router ospf 1

Summary-address 10.144.0.0 255.240.0.0

Also, will this actually do what I want or will the command “

Thanks for the help!

Our topology:

Layer3 switches (6509s and 4506s) with WAN connection to AT&T MPLS cloud to other sites. We are running OSPF at each site and redistributing tagged routes to AT&T’s router for redistribution across their BGP back into our OSPF at each site.

Example of our routing config at each site:

router ospf 1

router-id 10.152.200.2

log-adjacency-changes

auto-cost reference-bandwidth 10000

**redistribute connected subnets tag 30**

redistribute static subnets route-map STATIC-OSPFredistribute static subnets route-map STATIC-OSPF

passive-interface default

no passive-interface Vlan300

no passive-interface Vlan600

network 10.144.0.0 0.15.255.255 area 0

network 10.250.152.0 0.0.0.255 area 0

route-map STATIC-OSPF permit 10

match tag 30

One of our sites has a ton of subnets that are being advertised and I need to summarize the routes being redistributed to AT&T’s WAN router.

A

**sho ip route**connected displays over a 100 connected subnets which are being redistributed:#sho ip route connected

10.0.0.0/8 is variably subnetted, 102 subnets, 5 masks

C 10.152.212.0/24 is directly connected, Vlan212

C 10.152.200.0/22 is directly connected, Vlan200

C 10.152.205.0/24 is directly connected, Vlan205

C 10.250.152.0/24 is directly connected, Vlan250

C 10.152.250.0/24 is directly connected, Vlan600

C 10.152.18.0/24 is directly connected, Vlan18

C 10.152.19.0/24 is directly connected, Vlan19

C 10.152.16.0/24 is directly connected, Vlan16

C 10.152.17.0/24 is directly connected, Vlan17

C 10.152.22.0/24 is directly connected, Vlan22

C 10.152.23.0/24 is directly connected, Vlan23

C 10.152.20.0/24 is directly connected, Vlan20

C 10.152.21.0/24 is directly connected, Vlan21

C 10.152.26.0/24 is directly connected, Vlan26

C 10.152.27.0/24 is directly connected, Vlan27

C 10.152.24.0/24 is directly connected, Vlan24

C 10.152.25.0/24 is directly connected, Vlan25

C 10.152.30.0/24 is directly connected, Vlan30

C 10.152.31.0/24 is directly connected, Vlan31

C 10.152.28.0/24 is directly connected, Vlan28

C 10.152.29.0/24 is directly connected, Vlan29

C 10.152.255.253/32 is directly connected, Loopback100

C 10.152.0.0/24 is directly connected, Vlan300

C 10.152.255.254/32 is directly connected, Loopback101

C 10.152.6.0/24 is directly connected, Vlan6

C 10.152.7.0/24 is directly connected, Vlan7

C 10.152.5.0/24 is directly connected, Vlan5

C 10.152.10.0/24 is directly connected, Vlan10

C 10.152.11.0/24 is directly connected, Vlan11

C 10.152.8.0/24 is directly connected, Vlan8

C 10.152.9.0/24 is directly connected, Vlan9

C 10.152.14.0/24 is directly connected, Vlan14

C 10.152.15.0/24 is directly connected, Vlan15

C 10.152.12.0/24 is directly connected, Vlan12

C 10.152.13.0/24 is directly connected, Vlan13

C 10.152.50.0/24 is directly connected, Vlan50

C 10.152.51.0/24 is directly connected, Vlan51

C 10.152.48.0/24 is directly connected, Vlan48

C 10.152.49.0/24 is directly connected, Vlan49

C 10.152.54.0/24 is directly connected, Vlan54

C 10.152.55.0/24 is directly connected, Vlan55

C 10.152.52.0/24 is directly connected, Vlan52

C 10.152.53.0/24 is directly connected, Vlan53

C 10.152.58.0/24 is directly connected, Vlan58

C 10.152.59.0/24 is directly connected, Vlan59

C 10.152.56.0/24 is directly connected, Vlan56

C 10.152.57.0/24 is directly connected, Vlan57

C 10.152.34.0/24 is directly connected, Vlan34

C 10.152.35.0/24 is directly connected, Vlan35

C 10.152.32.0/24 is directly connected, Vlan32

C 10.152.33.0/24 is directly connected, Vlan33

C 10.152.38.0/24 is directly connected, Vlan38

C 10.152.39.0/24 is directly connected, Vlan39

C 10.152.36.0/24 is directly connected, Vlan36

C 10.152.37.0/24 is directly connected, Vlan37

C 10.152.42.0/24 is directly connected, Vlan42

C 10.152.43.0/24 is directly connected, Vlan43

C 10.152.40.0/24 is directly connected, Vlan40

C 10.152.41.0/24 is directly connected, Vlan41

C 10.152.46.0/24 is directly connected, Vlan46

C 10.152.47.0/24 is directly connected, Vlan47

C 10.152.44.0/24 is directly connected, Vlan44

C 10.152.208.253/32 is directly connected, Loopback0

C 10.152.45.0/24 is directly connected, Vlan45

C 10.152.82.0/24 is directly connected, Vlan82

C 10.152.80.0/24 is directly connected, Vlan80

C 10.152.81.0/24 is directly connected, Vlan81

C 10.152.102.0/24 is directly connected, Vlan102

C 10.152.100.0/24 is directly connected, Vlan100

C 10.152.101.0/24 is directly connected, Vlan101

I’m trying to figure out which command I need to use: the

**range**command or the**summary-address**command.Should I add

Router ospf 1

Area 0 range 10.144.0.0 255.240.0.0

OR

Router ospf 1

Summary-address 10.144.0.0 255.240.0.0

Also, will this actually do what I want or will the command “

**redistribute connected subnets tag 30**” still redistribute all 100+ connected subnets?Thanks for the help!

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