Want your own Tech/Cert Blog?
Colby over at AlwaysTheNetwork.com has started a new website called CertBlogs.com for people looking to start a blog dedicated to networking, certifications, virtualization, or any other technologically related topic. Here’s a snippet from his blog post for some more info…
I had an idea last night and decided to run with it. I’m starting a site to host tech blogs, like wordpress or blogger, but strictly for tech stuff. Not sure if people will be into it, but figured why not. It’s all WordPress, and will likely stay that way. So far all I have is the name and a barebones setup. I’d like you guys to tell me what you think and maybe test it all out.
Here’s some more information on it directly from his blog. I think it’s an awesome idea and hope more people jump on board!
Enjoy!
Busy, busy, busy…
Sorry for the incredible lack of updates recently. It’s been a few months since my last one, and that’s largely because I’m back at work for my co-op semester so that’s keeping me quite busy.
On the plus side of that though, I’ve had the chance to expand the 3750 stack at work with a third 3750, added a new 2960 to the edge, and I’ve been getting my feet wet on a Juniper SA 2500, which I have to say is very awesome. The capabilities of the SA 2500 are very impressive.
This summer I’ve also taken it upon myself to revamp the STP and VTP configurations as well, to hopefully optimize them a little more, and secure them more. I’ve also got a few other little changes I’ll be making as well as some projects we have to finish at work.
Unfortunately this means that my lab/tutorial posts will be largely few and far between but I’m hoping to get a few in about the SA 2500 and a few other things I’ve been working on.
Until next time…
OSPF and EIGRP Route Redistribution/Filtering Lab – Before Redistribution
Well after a rather busy few weeks of studying and exams, the semester is coming to a close, which means I”ll have tons more time to dedicated to labbing stuff out! With that being said, I’m going to finally finish this lab in particular, and move on to some more basic, shorter labs for a little while.
When I first introduced this lab I noticed a few errors after I reread what I posted and walked through it, so you can check out the intro post here to get some background on what it is we’re doing. Now on with the configs, of which I will only post the significant parts of and in a “before redistribution” and “after redistribution” fashion.
HQ:
interface Loopback2
ip address 2.2.2.1 255.255.255.0
!
interface Loopback3
ip address 3.3.3.1 255.255.255.0
!
interface Loopback7
ip address 7.7.7.1 255.255.255.0
!
interface FastEthernet0/0
description TO_OAKVILLE
ip address 64.30.28.1 255.255.255.252
duplex auto
speed auto
!
interface FastEthernet1/0
description TO_ETOBICOKE
ip address 129.66.100.1 255.255.255.252
ip ospf network point-to-point
duplex auto
speed auto
!
interface Ethernet2/0
description TO_BRAMPTON
ip address 20.108.68.1 255.255.255.252
half-duplex
!
interface Ethernet2/1
description TO_TORONTO
ip address 205.61.99.1 255.255.255.252
ip ospf network point-to-point
half-duplex
!
interface Ethernet2/2
description TO_ISP
ip address 13.4.2.2 255.255.255.252
half-duplex
In the above section of the config we have the interfaces. Not too much new or spectacular here, but I thought I would post it as it will be the only interface configuration I will post, the rest of the routers are pretty much the same thing. The part we’re interested in, and primarily on the HQ router, is the EIGRP and OSPF configuration…
HQ:
router eigrp 100
redistribute static
network 2.2.2.0 0.0.0.255
network 3.3.3.0 0.0.0.255
network 7.7.7.0 0.0.0.255
network 20.108.68.0 0.0.0.3
network 64.30.28.0 0.0.0.3
no auto-summary
!
router ospf 1
router-id 7.7.7.1
log-adjacency-changes
network 7.7.7.0 0.0.0.255 area 0
network 129.66.100.0 0.0.0.255 area 0
network 205.61.99.0 0.0.0.3 area 0
default-information originate
!
ip route 0.0.0.0 0.0.0.0 13.4.2.1
In the above section of the config, you’ll notice we’ve activated the two interfaces facing Etobicoke and Toronto under the OSPF process, and the two interfaces facing Oakville and Brampton are activated under the EIGRP process. Pretty standard stuff there as well, although you’ll notice the default-information originate command under the OSPF config, and the redistribute static command under the EIGRP config. Both of those commands tell the router to inject the default route I entered (ip route 0.0.0.0 0.0.0.0 13.4.2.1) into each process and advertise that out to it’s neighbours.
There are 2 or 3 ways of injecting a default route into EIGRP, but I chose the redistribute static command as it’s fairly simple to remember (not to say the others aren’t either).
Etobicoke:
Gateway of last resort is 129.66.100.1 to network 0.0.0.0
1.0.0.0/24 is subnetted, 1 subnets
C 1.1.1.0 is directly connected, Loopback1
O IA 192.168.60.0/24 [110/2] via 192.168.1.2, 00:05:57, FastEthernet0/0
4.0.0.0/24 is subnetted, 1 subnets
O IA 4.4.4.0 [110/2] via 192.168.1.2, 00:05:57, FastEthernet0/0
205.61.99.0/30 is subnetted, 1 subnets
O 205.61.99.0 [110/2] via 192.168.1.2, 00:05:57, FastEthernet0/0
172.17.0.0/24 is subnetted, 1 subnets
C 172.17.70.0 is directly connected, Loopback70
7.0.0.0/32 is subnetted, 1 subnets
O 7.7.7.1 [110/2] via 129.66.100.1, 00:05:57, FastEthernet1/0
129.66.0.0/30 is subnetted, 1 subnets
C 129.66.100.0 is directly connected, FastEthernet1/0
O IA 192.168.50.0/24 [110/2] via 192.168.1.2, 00:05:58, FastEthernet0/0
192.168.1.0/30 is subnetted, 1 subnets
C 192.168.1.0 is directly connected, FastEthernet0/0
O*E2 0.0.0.0/0 [110/1] via 129.66.100.1, 00:05:58, FastEthernet1/0
The output shown above is the route table from the Etobicoke router. As you can see the routes from HQ and Toronto are all successfully being advertised to Etobicoke. You’ll also notice the OSPF External Type 2 route (signified by the O*E2, with the * meaning it is the candidate default route) is successfully being passed through the OSPF network like we’d hoped. Likewise, you’ll also see the same in the output below from the Oakville router (except using EIGRP instead of OSPF).
Oakville:
Gateway of last resort is 64.30.28.1 to network 0.0.0.0
2.0.0.0/24 is subnetted, 1 subnets
D 2.2.2.0 [90/156160] via 64.30.28.1, 00:34:39, FastEthernet0/0
3.0.0.0/24 is subnetted, 1 subnets
D 3.3.3.0 [90/156160] via 64.30.28.1, 00:34:39, FastEthernet0/0
64.0.0.0/30 is subnetted, 1 subnets
C 64.30.28.0 is directly connected, FastEthernet0/0
20.0.0.0/30 is subnetted, 1 subnets
D 20.108.68.0 [90/284160] via 64.30.28.1, 00:34:39, FastEthernet0/0
172.16.0.0/23 is subnetted, 1 subnets
D 172.16.4.0 [90/412160] via 64.30.28.1, 00:33:07, FastEthernet0/0
7.0.0.0/24 is subnetted, 1 subnets
D 7.7.7.0 [90/156160] via 64.30.28.1, 00:34:39, FastEthernet0/0
10.0.0.0/8 is variably subnetted, 4 subnets, 2 masks
D 10.10.0.0/23 [90/412160] via 64.30.28.1, 00:33:08, FastEthernet0/0
C 10.1.80.0/24 is directly connected, Loopback80
C 10.1.100.0/24 is directly connected, Loopback100
C 10.1.200.0/24 is directly connected, Loopback200
D*EX 0.0.0.0/0 [170/284160] via 64.30.28.1, 00:34:40, FastEthernet0/0
The last few snippets will show how to do some of the things in the requirements outlined in the intro, mainly advertising loopbacks with the actual mask in OSPF, and stopping the VLAN interfaces from sending/receiving route updates and hellos.
Etobicoke (stop hellos from being sent/received out VLANs):
router ospf 1
router-id 1.1.1.1
passive-interface default
no passive-interface FastEthernet0/0
no passive-interface FastEthernet1/0
The passive-interface default command tells the router not to send or receive hellos on every interface on the router, which will of course shutdown the neighbourships between the routers, so to fix that we simple enter the no passive-interface <interface>, which will fix everything. These concepts are the same whether you’re using OSPF or EIGRP, so for the sake of time and space, I won’t post a snippet from another router.
Now, to advertise the loopbacks with their actual masks under OSPF, we need to enter the ip ospf network point-to-point command. Doing so would tell a router, for example, to advertise the network 192.168.1.0/24, as a /24. If we don’t do this the network would be advertised as a single host route, with a /32. Below is an example…
Toronto:
interface Loopback4
ip address 4.4.4.4 255.255.255.0
ip ospf network point-to-point
That concludes the “Before redistribution” part of the lab, in a few days I will post up the commands necessary to redistribute the routes, and the final configs.