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Posts tagged CCNP
Quick BGP Challenge #1
May 12th
This is the first little challenge I’m posting on here. If you frequent the forums, you likely saw the one I had for OSPF. I thought of another challenge while talking to a buddy. Here’s the topology:
Make R1 prefer the path through R3 for the 192.168.1.0/24 network. The configuration must be on R1. Do not use Weight or Local Preference to accomplish this. Assume that all previous configuration is correct.
This one is a little different than the OSPF challenge in that there are many ways to accomplish it. I’ve thought of a few, I want to see what everyone else comes up with.
Go!
OSPF Lab #1 Tasks
May 12th
This is the first OSPF post I’ll be doing for CCIE lab preparation. Sorry guys, I’ve been slacking with updates. Today I’m posting the tasks, then tomorrow or the day after I’ll post the walkthrough. If any of you work on this before the walkthrough, leave a comment.
Here’s the topology:
Click here for the initial configs
Here are the tasks:
1. Configure R1′s s0/0.102 interface and R2′s s0/0.201 interface in area 12, this area should not receive any Type 5 LSAs. Configure R1′s s0/0.103 interface and R3′s s0/0.301 interface in area 13, R1 should only receive a default route from R3, no other OSPF routes should be in R1′s RIB (from R3). Do not use network statements to accomplish this task.
Weekly Open Ended Question #12
May 5th
The answer to the eleventh question has been added to the post.
Twelfth question:
What are BPDU Filter and BPDU Guard? How do they differ and when are they used?
Please post answers in the comments (without Googling)!
Simple IPv6 Tutorial
Apr 20th
Today we’ll configure a basic IPv6 network. I’m not a big fan of IPv6. I’ve never used it in the real world, so it’s hard for me to keep it in my head, but I’ve been studying the hell out of it for the Written, so here goes.
We have a simple topology, only three routers. We will be running OSFPv3 on our serial links and loopbacks. Here’s our topology:
(Click image for fullsize)
First we’ll configure our IPv6 addresses:
R1: R1(config)#ipv6 unicast-routing R1(config)#int s0/0 R1(config-if)#ip add 10.1.12.1 255.255.255.0 R1(config-if)#ipv6 add 10:1:1:12::1/64 R1(config-if)#no shut R2: R2(config)#ipv6 unicast-routing R2(config)# int s0/0 R2(config-if)#ip add 10.1.12.2 255.255.255.0 R2(config-if)#ipv6 add 10:1:1:12::2/64 R2(config-if)#no shut R2(config-if)#exit R2(config)#int s0/1 R2(config-if)#ip add 10.1.23.2 255.255.255.0 R2(config-if)#ipv6 add 10:1:1:23::2/64 R2(config-if)#no shut R3: R3(config)#ipv6 unicast-routing R3(config-if)#int s0/1 R3(config-if)#ip add 10.1.23.3 255.255.255.0 R3(config-if)#ipv6 add 10:1:1:23::3/64 |
The first thing we do on each router is enable IPv6 routing. Then we give the interface an IPv4 address and finally an IPv6 address.
Let’s verify connectivity from R2:
Serial0/0 is up, line protocol is up
IPv6 is enabled, link-local address is FE80::C001:71FF:FE12:0
Global unicast address(es):
10:1:1:12::2, subnet is 10:1:1:12::/64
Joined group address(es):
FF02::1
FF02::2
FF02::1:FF00:2
FF02::1:FF12:0
MTU is 1500 bytes
ICMP error messages limited to one every 100 milliseconds
ICMP redirects are enabled
ND DAD is enabled, number of DAD attempts: 1
ND reachable time is 30000 milliseconds
Hosts use stateless autoconfig for addresses.
Serial0/1 is administratively down, line protocol is down
IPv6 is enabled, link-local address is FE80::C001:71FF:FE12:0 [TEN]
Global unicast address(es):
10:1:1:23::2, subnet is 10:1:1:23::/64 [TEN]
Joined group address(es):
FF02::1
FF02::2
FF02::1:FF00:2
FF02::1:FF12:0
MTU is 1500 bytes
ICMP error messages limited to one every 100 milliseconds
ICMP redirects are enabled
ND DAD is enabled, number of DAD attempts: 1
ND reachable time is 30000 milliseconds
Hosts use stateless autoconfig for addresses.
R2#sh ipv int b
Serial0/0 [up/up]
FE80::C001:71FF:FE12:0
10:1:1:12::2
Serial0/1 [up/up]
FE80::C001:71FF:FE12:0
10:1:1:23::2
R2#ping 10:1:1:12::1
Sending 5, 100-byte ICMP Echos to 10:1:1:12::1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/2/4 ms
R2#ping 10:1:1:23::3
Sending 5, 100-byte ICMP Echos to 10:1:1:23::3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 0/3/12 ms |
We have connectivity between interfaces on the same subnet.
Now we’ll configure our loopbacks and OSPFv3:
R1: R1(config-if)#int lo0 R1(config-if)#ipv6 add 1:1:1::1/64 R1(config-if)#ipv6 ospf 20 area 0 R1(config-if)#int s0/0 R1(config-if)#ipv6 ospf 20 area 0 R2: R2(config)#int lo0 R2(config-if)#ipv6 add 2:2:2::2/64 R2(config-if)#ipv6 ospf 20 area 0 R2(config-if)#int s0/0 R2(config-if)#ipv6 ospf 20 area 0 R2(config-if)#int s0/1 R2(config-if)#ipv6 ospf 20 area 0 R3: R3(config)#int lo0 R3(config-if)#ipv6 add 3:3:3::3/64 R3(config-if)#ipv6 ospf 20 area 0 R3(config-if)#int s0/1 R3(config-if)#ipv6 ospf 20 area 0 |
With v6 we enable OSPF directly under the interface on which it runs.
Troubleshooting Lab #6
Apr 7th
First lab with our new topology. I’m excited! This should be an easy one. When functioning correctly, Customer “a” connects to AS 6500 using MPLS VPNs and running OSPF with the provider between sites. Site 2 (CE2a) has internet access through a physical connection to AS 6500s global RIB, it also has a GRE tunnel to PE1 which connects to the MPLS VPN. Customer “b” has a similar configuration. Customer “b” is using EIGRP. Both customers have a single “internet” circuit which is reachable from only one site, all internet traffic from the other site will go over the WAN first.
The issue today is users in VLAN 40 are having issues accessing the internet (87.3.85.1), determine why.
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