One Network Engineer's journey to the CCIE

I have now run into the same issue twice in the past two weeks with IOS. I am very accustomed to using Ctrl+Z, to exit config mode completely and move onto to doing show commands. Yesterday, I was doing some labs and after configuring IPv6 RIP on an interface, I started typing a “show” command, realized I was in config mode, so hit Ctrl+Z to exit and then be able to continue with my show commands.

Rack1R1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Rack1R1(config)#int serial 0/0
Rack1R1(config-if)#ipv6 rip RIPNG enable
Rack1R1(config-if)#sh^Z

*Mar 1 07:39:35.966: %LINK-5-CHANGED: Interface Serial0/0, changed state to administratively down
*Mar 1 07:39:36.966: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to down

After having this happen to me twice, I looked it up and found this note here

If you use Ctrl-Z at the end of a command line in which a valid command has been typed, that command will be added to the running configuration file. In other words, using Ctrl-Z is equivalent to hitting the Enter (Carriage Return) key before exiting. For this reason, it is safer to end your configuration session using the end command. Alternatively, you can use the Ctrl-C key combination to end your configuration session without sending a Carriage Return signal.

Needless to say, i will be more careful and try using Ctrl+C or the “end” command instead of Ctrl+Z.

When starting with the IPv6 portion of Vol 1, one of the tasks is to enable IPv6 on SW1 and SW3. When trying to do this, I forgot how to enable IPv6 on the Catalyst switch line.

For starters, I went into the switch and I had forgotten of the procedure necessary to have IPv6 working on the switches. As you can see, I tried various commands to enable IPv6 but to no avail.

Enter configuration commands, one per line. End with CNTL/Z.
Rack1SW1(config)#int vlan 67
Rack1SW1(config-if)#ip?
ip

Rack1SW1(config-if)#ipv6 enable ?
% Unrecognized command
Rack1SW1(config-if)#exit
Rack1SW1(config)#ipv
Rack1SW1(config)#ipv6 un
Rack1SW1(config)#ipv6 ?
% Unrecognized command
Rack1SW1(config)#exit

Rack1SW1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Rack1SW1(config)#ipv?
% Unrecognized command
Rack1SW1(config)#exit

Rack1SW1#sh license
^
% Invalid input detected at ‘^’ marker.

Rack1SW1#sh version
Cisco IOS Software, C3560 Software (C3560-ADVIPSERVICESK9-M), Version 12.2(46)SE, RELEASE SOFTWARE (fc2)
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Thu 21-Aug-08 15:26 by nachen
Image text-base: 0×00003000, data-base: 0x01A00000

After a little bit of digging, I remembered that the way to enable IPv6 on the 3560′s is via the SDM.

Rack1SW1#show sdm prefer
The current template is “desktop default” template.
The selected template optimizes the resources in
the switch to support this level of features for
8 routed interfaces and 1024 VLANs.

number of unicast mac addresses: 6K
number of IPv4 IGMP groups + multicast routes: 1K
number of IPv4 unicast routes: 8K
number of directly-connected IPv4 hosts: 6K
number of indirect IPv4 routes: 2K
number of IPv4 policy based routing aces: 0
number of IPv4/MAC qos aces: 0.5K
number of IPv4/MAC security aces: 1K

Rack1SW1#conf t

Rack1SW1(config)#sdm prefer ?
access Access bias
default Default bias
dual-ipv4-and-ipv6 Support both IPv4 and IPv6
ipe IPe bias
routing Unicast bias
vlan VLAN bias

Rack1SW1(config)#sdm prefer dual-ipv4-and-ipv6 ?
default Default bias
routing Unicast bias
vlan VLAN bias

Rack1SW1(config)#sdm prefer dual-ipv4-and-ipv6 routing
Changes to the running SDM preferences have been stored, but cannot take effect
until the next reload.
Use ‘show sdm prefer’ to see what SDM preference is currently active.
Rack1SW1(config)#exit
Rack1SW1#wri mem

Rack1SW1#show sdm prefer
The current template is “desktop default” template.
The selected template optimizes the resources in
the switch to support this level of features for
8 routed interfaces and 1024 VLANs.

number of unicast mac addresses: 6K
number of IPv4 IGMP groups + multicast routes: 1K
number of IPv4 unicast routes: 8K
number of directly-connected IPv4 hosts: 6K
number of indirect IPv4 routes: 2K
number of IPv4 policy based routing aces: 0
number of IPv4/MAC qos aces: 0.5K
number of IPv4/MAC security aces: 1K

On next reload, template will be “desktop IPv4 and IPv6 routing” template.

Rack1SW1#reload
Proceed with reload? [confirm]

*Mar 1 05:08:34.051: %SYS-5-RELOAD: Reload requested by console. Reload Reason: Reload command.

After rebooting, everything is set and ready for IPv6 traffic.

Rack1SW1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Rack1SW1(config)#ipv6 unicast-routing
Rack1SW1(config)#exit
Rack1SW1#wri mem
Building configuration…
[OK]
Rack1SW1#
*Mar 1 00:01:39.270: %SYS-5-CONFIG_I: Configured from console by console
Rack1SW1#conf t
Rack1SW1(config)#int vlan 67
Rack1SW1(config-if)#ipv6 enable
Rack1SW1(config-if)#int gig0/3
Rack1SW1(config-if)#ipv6 enable
Rack1SW1(config-if)#^Z
Rack1SW1#
*Mar 1 00:09:58.426: %SYS-5-CONFIG_I: Configured from console by console

While doing my Multicast labs, I ran into an OSPF issue that I have seen before while doing OSPF labs. OSPF tends to be troublesome over some interfaces when using Dynamips due to MTU issues. Here are some logs from my device R6:

*Mar 1 00:20:40.815: %OSPF-5-ADJCHG: Process 1, Nbr 150.1.7.7 on FastEthernet0/0.67 from EXSTART to DOWN, Neighbor Down: Too many retransmissions
*Mar 1 00:21:40.819: %OSPF-5-ADJCHG: Process 1, Nbr 150.1.7.7 on FastEthernet0/0.67 from DOWN to DOWN, Neighbor Down: Ignore timer expired

The cause of this issue is an MTU mismatch preventing a full OSPF adjacency from happening.

Rack1R6#sh int fastEthernet 0/0.67
FastEthernet0/0.67 is up, line protocol is up
Hardware is Gt96k FE, address is c207.09cf.0000 (bia c207.09cf.0000)
Internet address is 155.1.67.6/24
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 1000 usec,

Rack1SW1#sh int vlan 67
Vlan67 is up, line protocol is up
Hardware is EtherSVI, address is 0023.05e3.a8c3 (bia 0023.05e3.a8c3)
Internet address is 155.1.67.7/24
MTU 1504 bytes, BW 1000000 Kbit, DLY 10 usec,

The first way to correct the issue is rather obvious, which is to make the MTU’s match on the interfaces. Unfortunately, I was unable to do this on either device.

Rack1R6#conf t
Rack1R6(config)#int fastEthernet 0/0.67
Rack1R6(config-subif)#mtu 1504
% Interface FastEthernet0/0 does not support user settable mtu.

Rack1SW1#conf t
Rack1SW1(config)#int vlan 67
Rack1SW1(config-if)#ip mtu ?
<68-1504> MTU (bytes)

Rack1SW1(config-if)#ip mtu 1500
% ip mtu is not supported on this interface

There is another way to correct the problem, which is the “ip ospf mtu-ignore” command. You take the interface from the error message, in this case “FastEthernet0/0.67″ and apply the command to it.

Rack1R6#conf t
Rack1R6(config)#int fastEthernet 0/0.67
Rack1R6(config-subif)#ip ospf mtu-ignore

*Mar 1 00:21:48.291: %OSPF-5-ADJCHG: Process 1, Nbr 150.1.7.7 on FastEthernet0/0.67 from LOADING to FULL, Loading Done

To read more about the solution, please go here or read below:

ip ospf mtu-ignore

To disable OSPF MTU mismatch detection on receiving DBD packets, use the ip ospf mtu-ignore command in interface configuration mode. To reset to default, use the no form of this command.

OSPF checks whether neighbors are using the same MTU on a common interface. This check is performed when neighbors exchange Database Descriptor (DBD) packets. If the receiving MTU in the DBD packet is higher than the IP MTU configured on the incoming interface, OSPF adjacency will not be established.

I have been making some good progress on the Vol 1 workbook. Petr Lapukhov’s How to pass the CCIE R&S with INE’s 4.0 Training Program guide estimates 8 weeks to complete Vol 1, i am proud to say that I am more than halfway done after only 5 days. In the next 11 weeks I will have to complete Vol. 1, do as much of Vol 2 as I can as well as watching the Advanced Technologies Video on Demand. To be quite honest, I think I have set myself up at a good pace and cannot wait for the bootcamp to be here.

Here are the sections I have completed thus far:
Completed:
Bridging & Switching: 1.1-1.15
Frame-Relay: 2.1-2.8
IP Routing: 3.1-3.11
RIP: 4.1-4.11
EIGRP: 5.1-5.10
OSPF: 6.1-6.14
BGP: 7.1-7.6

To be completed:
BGP: 7.7-7.12
IPv6: 9.1-9.9
Multicast: 8.1-8.10
MPLS VPN: 14.1-14.7

Just completed the INE IP Routing section of Vol 1. I feel I am making very good time on these Vol 1 labs as in INE has suggested it would take 8 weeks to get wholly familiar with these topics and I have done the first 3 in 3 days. I am pretty happy with my progress and plan to keep going forward. Overall, my plan is to complete the aforementioned sections of Vol 1, then move onto Vol 2 and work that while also listening to the Advanced Technologies Class on demand and having both of them complete before going to my 10-day bootcamp. WIth only 11 weeks left, it sounds do-able, but you never know. Either way, I will keep this blog updated with progress. Thank you.

I have started my studying again and have completed the INE Workbook vol. 1 section 1.1 through 1.15. The topics in this section are all review and to be honest are a section that I work on quite a bit on a daily basis, but its always good to review. The included sections are:
1.1 Layer 2 Access Switchports
1.2 Layer 2 Dynamic Switchports
1.3 ISL Trunking
1.4 802.1q Trunking
1.5 802.1q Native VLAN
1.6 Disabling DTP Negotiation
1.7 Router-on-a-stick
1.8 VTP
1.9 VTP Transparent
1.10 VTP pruning
1.11 VTP Prune-eligible list
1.12 Layer 2 Etherchannel
1.13 Layer 2 Etherchannel with PAgp
1.14 Layer 2 Etherchannel with LACP
1.15 Layer 3 Etherchannel

I look forward to moving onto the Frame Relay section, as it is one that I am not that familiar with. I have already completed this entire section once, but am reviewing as part of my study plan for the 10-day bootcamp I am attending in June. I plan on completing Vol 1 sections detailed in my previous post, as well as completing watching the Advanced Technologies Video on Demand from INE.com. If i have time left over, I will start some Vol 2 labs, just to be ahread before the class begins. I feel I have ample time to complete these goals before the actual class. Until tomorrow…..

I have signed up for the 10-day INE.com bootcamp in Seattle, WA from Jun 18th – Jun 29th, 2012. In order to be prepared for the bootcamp, they recommend you complete Vol 1 of their self-study material as well as the Advanced Technologies Video on Demand. I have done the key sections of Vol 1 as one of their guides had instructed. For those of you interested in what exactly I have done, here are the sections:

Bridging & Switching: 1.1-1.15
Frame-Relay: 2.1-2.8
IP Routing: 3.1-3.11
RIP: 4.1-4.11
EIGRP: 5.1-5.10
OSPF: 6.1-6.14
BGP: 7.1-7.12
IPv6: 9.1-9.9
Multicast: 8.1-8.10
MPLS VPN: 14.1-14.7

I have started watching the Advanced Technologies Video On Demand which consist of 81h 59min of Brian McGahan teaching a two-week course going over the fundamentals of what will be on the lab exam. I have about 3 months to prepare for the class and according to INE.com, I will need about 3-4 months after the class of self-prep to be truly prepared. Either way, I am trying to update this site more regularly as I back into studying hardcore.

It has been quite awhile since I have done anything CCIE related. I have started with watching the Intro video to the INE.com Advanced Technologies. To be honest, it was mostly a recap of stuff I have seen/heard before from the CCIE Written Class on Demand, but its good to hear again and remind myself of these things I have long forgotten. The things that stuck with me the most are the steps to success in this journey towards attaining the CCIE:

Step 1:Gain Basic understanding
Step 2:Gain basic hands-on experience to reinforce and expand your understand
Step 3:Gain an expert level of understanding
Step 4:Gain an expert level of hands-on experience

Brian McGahan also said something that I know is VERY true. “CCIE is not only a financial investment. Its also a time investment.” This rings so true for me as the time to study has become more scarce with so much going on in my personal as well as professional life. That being said, the CCIE is something important and something that I will begin to make the time for. As I write this on a Saturday night, I am at home listening to these videos instead of doing other things, so its a good start. Either way, until the next update.

I ran into some issues with section 3 of the INE Vol 1. For starters, I had my schedule pushed back a few days due to some issues with my SW4 device. For some reason, the console port stopped working all of a sudden. I tried a known-good cable and USB serial and it wasnt working. I contacted the eBay seller who I bought the devices from, Candela Networks, who happens to be conveniently located here in NJ about a 20 min drive from my house. I went to their warehouse and a tech tested the device and of course it works all of a sudden. He says he did nothing, but I dont know if I believe him The important thing is that the console works again and I was able to continue working on my labs making some decent progress.

The true test will be next week when I goto Chicago for work purposes. I will be there for 1 week and will need to work remotely on my rack. I have toyed with the idea of getting rack space and putting these devices on the internet, but I have reservations about these types of changes. I prefer to have them physically close so I can do whatever changes are necessary. Either way, I am continuing with the lab studies and will update with any relevant.