Category Archives: Misc

2013 Wrap up

2013 has been a stellar year on a number of levels for me. In January I sat my CCIE R&S for the second time and passed at last. November this year I took and passed the JNCIE-SP in my first attempt.

I travelled to more places this year than I’ve ever done. I’ve managed to see Greece, Belgium, The Netherlands, Hungary, Germany, and Denmark – Some of these places I’ve already been to, but there were a few new on the list.

Blog-wise I’m a few hundred short of 180 000 views this year. I’ve almost totalled half a million in total since I started. Not bad for what is essentially my own notes.

Post-wise my old simple posts are still pulling major numbers in. My top three posts are :

  1. HSRP Object Tracking
  2. Access-lists vs prefix-lists
  3. MPLS L3VPN – Route Distinguisher vs Route Target vs VPN label

 

In the last 3 months the following three posts have already been increasing rapidly:

  1. L2VPN on Junos using CCC/Martini/Kompella
  2. So how does the JNCIE-SP compare to the CCIE R&S?
  3. Moving routes between a VRF and the global (default) RIB – Part 1 – Cisco IOS

 

In total I have published 267 posts and I still have 85 drafts! In fact I created 5 drafts alone in the last two weeks. If only I had the time to finish them…

Work-wise has been just as busy. I can’t go too much into in but rest assured I’m very busy on a day to day basis.

I plan a number of things for 2014. I plan to sit my CCIE SP lab and possibly go for the JNCIE-SEC too. I plan to work more on my python skills and who knows what else.

Hope your 2013 has been as good as mine and I wish all my readers the best for 2014!

Geek Humour

This came up on my twitter feed.

 

Someone had a bit of time to spare :)

 

Darrens-MacBook-Pro:~ darrenoconnor$ traceroute -m 100 216.81.59.173
traceroute to 216.81.59.173 (216.81.59.173), 100 hops max, 52 byte packets
 1  10.20.30.254 (10.20.30.254)  1.536 ms  5.857 ms  2.364 ms
 2  par8.the1.hso.uk.com (217.196.224.63)  34.726 ms  32.034 ms  29.593 ms
 3  89.248.31.242 (89.248.31.242)  30.738 ms  32.790 ms  30.813 ms
 4  eth-1-2-pcr2.the1.hso.uk.com (89.248.31.66)  33.241 ms  31.732 ms  30.269 ms
 5  ge-0-0-0.643.pgr1.the1.hso.uk.com (89.248.31.90)  30.403 ms  30.831 ms  30.572 ms
 6  10gigabitethernet1-1.core1.lon1.he.net (195.66.224.21)  39.180 ms  182.543 ms  92.774 ms
 7  10gigabitethernet2-4.core1.par2.he.net (72.52.92.42)  211.946 ms  246.535 ms  189.330 ms
 8  10gigabitethernet2-3.core1.ash1.he.net (72.52.92.86)  284.252 ms  227.281 ms  105.802 ms
 9  10gigabitethernet1-2.core1.atl1.he.net (184.105.213.110)  115.707 ms  122.671 ms  125.202 ms
10  216.66.0.26 (216.66.0.26)  122.004 ms  368.930 ms  310.685 ms
11  * * *
12  episode.iv (206.214.251.1)  311.114 ms *  156.018 ms
13  a.new.hope (206.214.251.6)  171.400 ms  159.435 ms *
14  * it.is.a.period.of.civil.war (206.214.251.9)  156.518 ms  296.157 ms
15  rebel.spaceships (206.214.251.14)  290.497 ms  199.703 ms  312.318 ms
16  striking.from.a.hidden.base (206.214.251.17)  159.896 ms  163.075 ms  174.722 ms
17  have.won.their.first.victory (206.214.251.22)  389.669 ms  300.441 ms  272.661 ms
18  against.the.evil.galactic.empire (206.214.251.25)  260.969 ms  155.293 ms *
19  * during.the.battle (206.214.251.30)  162.813 ms *
20  rebel.spies.managed (206.214.251.33)  280.752 ms  154.430 ms  160.661 ms
21  * to.steal.secret.plans (206.214.251.38)  155.220 ms  292.473 ms
22  * * to.the.empires.ultimate.weapon (206.214.251.41)  430.411 ms
23  the.death.star (206.214.251.46)  164.377 ms  159.828 ms  181.927 ms
24  an.armored.space.station (206.214.251.49)  386.890 ms  313.281 ms  348.824 ms
25  with.enough.power.to (206.214.251.54)  257.772 ms  165.174 ms  169.809 ms
26  destroy.an.entire.planet (206.214.251.57)  161.333 ms *  297.655 ms
27  pursued.by.the.empires (206.214.251.62)  234.606 ms  171.485 ms  160.942 ms
28  sinister.agents (206.214.251.65)  155.042 ms  211.949 ms  337.558 ms
29  princess.leia.races.home (206.214.251.70)  348.928 ms  302.142 ms  168.598 ms
30  aboard.her.starship (206.214.251.73)  269.518 ms  159.735 ms *
31  custodian.of.the.stolen.plans (206.214.251.78)  153.351 ms  429.375 ms  188.548 ms
32  that.can.save.her (206.214.251.81)  328.521 ms  253.633 ms  239.572 ms
33  people.and.restore (206.214.251.86)  157.389 ms  162.298 ms  165.251 ms
34  freedom.to.the.galaxy (206.214.251.89)  162.107 ms  201.800 ms  269.294 ms
35  0-------------------0 (206.214.251.94)  155.826 ms  248.209 ms  257.509 ms
36  0------------------0 (206.214.251.97)  162.547 ms  161.263 ms
37  0-----------------0 (206.214.251.102)  174.690 ms  357.441 ms  177.023 ms
38  0----------------0 (206.214.251.105)  265.276 ms  246.617 ms
39  0---------------0 (206.214.251.110)  154.193 ms *  261.325 ms
40  0--------------0 (206.214.251.113)  334.108 ms  387.358 ms  323.404 ms
41  0-------------0 (206.214.251.118)  365.551 ms  262.761 ms  276.147 ms
42  0------------0 (206.214.251.121)  258.407 ms  229.782 ms  154.227 ms
43  0-----------0 (206.214.251.126)  187.464 ms  367.916 ms  207.837 ms
44  0----------0 (206.214.251.129)  171.653 ms  160.855 ms  162.155 ms
45  0---------0 (206.214.251.134)  286.488 ms
46  0--------0 (206.214.251.137)  287.830 ms  305.328 ms  161.175 ms
47  0-------0 (206.214.251.142)  163.229 ms  193.517 ms  317.109 ms
48  0------0 (206.214.251.145)  194.226 ms  164.839 ms  374.419 ms
49  0-----0 (206.214.251.150)  192.069 ms *  153.536 ms
50  0----0 (206.214.251.153)  160.716 ms *  160.896 ms
51  0---0 (206.214.251.158)  282.271 ms  298.677 ms  194.065 ms
52  0--0 (206.214.251.161)  292.340 ms  306.083 ms  158.136 ms
53  0-0 (206.214.251.166)  155.467 ms  156.500 ms  339.900 ms
54  00 (206.214.251.169)  269.275 ms  161.149 ms  209.053 ms
55  i (206.214.251.174)  239.744 ms  256.089 ms  310.502 ms
56  by.ryan.werber (206.214.251.177)  219.954 ms  164.404 ms  215.458 ms
57  when.ccies.get.bored (206.214.251.182)  260.667 ms  153.757 ms *
58  ccie.38168 (206.214.251.185)  424.565 ms  280.190 ms  162.993 ms
59  fin (206.214.251.190)  155.971 ms *  154.775 ms

Some site stats

I’ve had my hits steadily growing almost every month since I started this blog, and I thought I would share some of those stats.

My first blog post was in October 2009. I was a fresh CCNP and not yet CCIP certified. – http://mellowd.co.uk/ccie/?p=3

Graph of monthly visitors since the start of the blog:

stats Some site stats

There was a bit of a dip when work become very hectic and I simply did not have time to create any content. Once I started writing again that quickly turned around :)

January 2012 I had a total of 11 430 hits! A new record for me :D – Must be my CCIE notes! I’ve got more to do, but time again is my enemy!

My busiest day so far was the 12th of January when I had 525 hits:

Stats Some site stats

I’ll hit the 150 000 views soon enough :D All I can say is, thanks to my readers :) Please continue to comment here and there, and if you see a mistake somewhere please correct me!

Know your IPv4 and IPv6 address ranges

We’re busy implementing IPv6 on our BGP edges and eventually in our core at the moment. It’s pretty easy in the IPv4 world to work out what addresses are what, but there are loads more in IPv6.

I’ve decided to list the current assigned and reserved IPv4 and IPv6 address spaces here. Note that this list is still a work in progress, especially on the IPv6 side of things.

Let’s start with IPv4. Most of you should know most of the reserved ranges, but there may be a few you didn’t know about.

IPv4

Reserved:
0.0.0.0/8 – RFC1700
127.0.0.0/8 – Loopback

Internal private ranges (RFC1918)
10.0.0.0/8
172.16.0.0/12
192.168.0.0/16

Documentation (RFC5737)
192.0.2.0/24
198.51.100.0/24
203.0.113.0/24

Multicast (RFC5771, RFC6034 & RFC2365)
224.0.0.0/8 – 239.0.0.0/8

‘Future use’ – will never be used
240.0.0.0/8 – 255.0.0.0/8

255.255.255.255 is reserved for limited broadcast (RFC919 and RFC922)

IPv6

Now let’s check IPv6. The current Global Unique (aka public IP) range is 2000::/3 – that means any address from 2000:0000:0000:0000:0000:0000:0000:0000 – 3FFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF is a global unique unicast address – However, RFC3849 deems it fit to assign 2001:0DB8::/32 as non-routable to be used for documentation. Why they couldn’t use a range outside 2000::/3 is beyond me.

The following are all reserved by the IEFT (RFC4291, RFC4048 and RFC3879)
0100::/8
0200::/7
0400::/6
0800::/5
1000::/4
4000::/3
6000::/3
8000::/3
A000::/3
C000::/3
E000::/4
F000::/5
F800::/6
FE00::/9
FEC0::/10

Unique Local Unicast addresses (RFC4193)
FC00::/7

Link Local Unicast addresses (RFC4291)
FE80::/10

Multicast addresses (RFC4291)
FF00::/8

Loopback address
::1

Default route
::/0

6to4 tunnels
2002::/16

Teredo (RFC4380)
2001::/32

Unspecified
::

I’m sure I may have missed some out, so please let me know if I have

Capture packets directly inside dynamips

I had no idea that dynagen could actually do this, but it’s pretty damn awesome. Dynagen/Dynamips can output any interface’s traffic directly to a .cap file ready to be read in tcpdump or Wireshark.

How do we do this?

Let’s take a simple topology. R2 and R4 are running OSPF with each other, directly connected via their Fa0/1 interfaces. I want to capture packets going in and out of R2′s interface.

Dynamips/Dynagen has started:

=> list
Name       Type       State      Server          Console
R2         7200       running    localhost:7200  2002
R4         7200       running    localhost:7200  2004

You start capturing like so:

=> capture R2 fa0/1 /tmp/R2.cap

Stop the capture:

=> no capture R2 fa0/1

We now have a file named R2.cap in the /tmp folder. We can open it either in tcpdump or Wireshark:

darreno@Zenoss:/tmp$ sudo tcpdump -r R2.cap
reading from file R2.cap, link-type EN10MB (Ethernet)
16:37:26.959354 IP 7.3.24.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello, length 56
16:37:28.930017 CDPv2, ttl: 180s, Device-ID 'R2', length 318
16:37:32.827991
16:37:36.959745 IP 7.3.24.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello, length 56
16:37:42.855127
16:37:46.930856 IP 7.3.24.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello, length 56
16:37:52.846687
16:37:56.940269 IP 7.3.24.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello, length 56
16:38:02.826550
16:38:06.943788 IP 7.3.24.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello, length 56
16:38:12.836321
16:38:16.947188 IP 7.3.24.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello, length 56
16:38:22.835339
16:38:26.932277 IP 7.3.24.2 > OSPF-ALL.MCAST.NET: OSPFv2, Hello, length 56
16:38:28.940528 CDPv2, ttl: 180s, Device-ID 'R2', length 318

wiresharkdynamips Capture packets directly inside dynamips

Very handy indeed!