Lot’s of great info here:
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Archive for July, 2009
short technology articles
Posted by Peter Kurdziel on July 28, 2009
Posted in Routing & Switching Lab | Leave a Comment »
I had to take some time off. I burnt myself out.
Posted by Peter Kurdziel on July 24, 2009
I decided I needed a few days off to rest for the last 50 days mega study-a-thon.
I think I was over doing it and I burnt myself out.
I also incorporated physical training (weight lifting) 3 times a week. I find it’s a great stress reliever and it super charges me.
Posted in Routing & Switching Lab | Leave a Comment »
Freemap – great free study tool
Posted by Peter Kurdziel on July 19, 2009
FreeMind – free mind mapping software
http://freemind.sourceforge.net/wiki/index.php/Main_Page
http://freemind.sourceforge.net/wiki/index.php/Download
I wish I started using this earlier.
Posted in Routing & Switching Lab | Leave a Comment »
ipv4 to ipv6
Posted by Peter Kurdziel on July 16, 2009
Decimal 150 1 3 3 Binary 1001 0110 0000 0001 0000 0011 0000 0011 in hex, they are 16 digit groupings for hex representations, 1001=9 0110=6 so forth, The results is 9601:0303 http://blog.ru.co.za/2009/03/19/converting-ipv4-to-ipv6/Converting from IPv4 to IPv6
is so easy, yet everyone seem to convert a IPv4 address to binary, then to IPv6. Why? Why waste time and do things the long way? Not cool. When would you need to do this? One specific use is IPv6 6-to-4 tunnels, which always concatenates 2002::/16 with the IPv4 address embedded. With Automatic 6-to-4-tunnels, your address format is as follow: 2002:<32 bit IPv4 site address in Hex>:<16 bit network number in Hex>::/64 The question is how to do the conversion. Firstly before starting I will assume everyone knows the following:
- Binary is a Base-2 numbering system, as it has only 0,1
- Decimal is a Base-10 numbering system, as it has 0,1,2,3,4,5,6,7,8,9
- Hexadecimal is a Base-16 numbering system, as it has 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F
| A | = | 10 |
| B | = | 11 |
| C | = | 12 |
| D | = | 13 |
| E | = | 14 |
| F | = | 15 |
- Each Octet (8 bits) “between the dot-thingys” denote 1 byte
- Two Tuples (1 Tuple = 4 bits = 1 Hex character) denotes 1 byte
Converting back from IPv6 to IPv4
Now to convert the same portion of the IPv6address 2002:C0A8:6301::1/64 back to IPv4, the reverse method would apply. Let me point one more thing about Base-16 out to understand why I’m doing what I am below: 160 = 1 161 = 16 Taking the portion C0A8:6301, first divide the address into 2 Tuple-groupings (2 Hex Characters) = C0 A8 63 01 Step1 > Take C0 and multiply the first character ‘C’ by 16 and the second character ‘0′ by 1. Add the two decimal values together to get the IPv4 decimal value IE: ((C=12)*16) + (0*1) = 192 Step2 > Repeat the same process with A8, IE: ((A=10)*16) + (8*1) = 168 Step3 > Repeat the same process with 63, IE: (6*16) + (3*1) = 99 Step4 > Repeat the same process with 01, IE: (0*16) + (1*1) = 1Posted in IPV6, Routing & Switching Lab | Leave a Comment »
Completed Narbiks multicasting labs
Posted by Peter Kurdziel on July 16, 2009
Moving on to IPV6.
Posted in Multicast, Routing & Switching Lab | Leave a Comment »
ROMmon Recovery for the Cisco 2600
Posted by Peter Kurdziel on July 15, 2009
http://www.cisco.com/en/US/products/hw/routers/ps259/products_tech_note09186a0080094a0b.shtml
rommon 1 > dir flash:
File size Checksum File name
5358032 bytes (0x51c1d0) 0x7b16 c2600-i-mz.122-10b.bin
rommon 2 >
is the image valid?
rommon 2 > boot flash:c2600-i-mz.122-10b.bin
or rommon 2 > confreg correct if necessary (0x2102)
rommon 3 > reset I had 3 routers crash today! Three different IOS's = bad checksum . What's going on? Hmmm a clue; *** System received a SegV exception ***ERROR: 'Segmentation Violation (SegV) Exceptions' are always related to software issues. TRY THIS: Please refer to the TAC Case Collection - SegV exceptions for troubleshooting. REFERENCE: For more information, see SegV Exceptions. http://www.ciscotaccc.com/kaidara-advisor/core/showcase?case=K21445274 Cause of SegV ExceptionsSegV exceptions are always software problems. It is possible for different software issues to cause a SegV exception, such as:
- Access to an invalid memory address
- Write access to a read-only memory region
- A jump to an invalid PC (often 0x0)
Posted in Real World, Routing & Switching Lab, Troubleshooting | Leave a Comment »
Day 60 – where does the time go?
Posted by Peter Kurdziel on July 15, 2009
So much to do and so little time. The nerves are starting to kick in. I will be ready. 
Wrapping up multicasting today. Then moving on to IPV6.
Posted in Routing & Switching Lab | Leave a Comment »
IP Protocol Numbers
Posted by Peter Kurdziel on July 13, 2009
http://www.iana.org/assignments/protocol-numbers/
Note: In the Internet Protocol version 4 (IPv4) [RFC791] there is a field
called "Protocol" to identify the next level protocol. This is an 8
bit field. In Internet Protocol version 6 (IPv6) [RFC1883], this field
is called the "Next Header" field.
Registry:
Decimal Keyword Protocol References
------- --------------- --------------------------------------- ------------------
0 HOPOPT IPv6 Hop-by-Hop Option [RFC1883]
1 ICMP Internet Control Message [RFC792]
2 IGMP Internet Group Management [RFC1112]
3 GGP Gateway-to-Gateway [RFC823]
4 IP IP in IP (encapsulation) [RFC2003]
5 ST Stream [RFC1190][RFC1819]
6 TCP Transmission Control [RFC793]
7 CBT CBT [Ballardie]
8 EGP Exterior Gateway Protocol [RFC888][DLM1]
9 IGP any private interior gateway [IANA]
(used by Cisco for their IGRP)
10 BBN-RCC-MON BBN RCC Monitoring [SGC]
11 NVP-II Network Voice Protocol [RFC741][SC3]
12 PUP PUP [PUP][XEROX]
13 ARGUS ARGUS [RWS4]
14 EMCON EMCON [BN7]
15 XNET Cross Net Debugger [IEN158][JFH2]
16 CHAOS Chaos [NC3]
17 UDP User Datagram [RFC768][JBP]
18 MUX Multiplexing [IEN90][JBP]
19 DCN-MEAS DCN Measurement Subsystems [DLM1]
20 HMP Host Monitoring [RFC869][RH6]
21 PRM Packet Radio Measurement [ZSU]
22 XNS-IDP XEROX NS IDP [ETHERNET][XEROX]
23 TRUNK-1 Trunk-1 [BWB6]
24 TRUNK-2 Trunk-2 [BWB6]
25 LEAF-1 Leaf-1 [BWB6]
26 LEAF-2 Leaf-2 [BWB6]
27 RDP Reliable Data Protocol [RFC908][RH6]
28 IRTP Internet Reliable Transaction [RFC938][TXM]
29 ISO-TP4 ISO Transport Protocol Class 4 [RFC905][RC77]
30 NETBLT Bulk Data Transfer Protocol [RFC969][DDC1]
31 MFE-NSP MFE Network Services Protocol [MFENET][BCH2]
32 MERIT-INP MERIT Internodal Protocol [HWB]
33 DCCP Datagram Congestion Control Protocol [RFC4340]
34 3PC Third Party Connect Protocol [SAF3]
35 IDPR Inter-Domain Policy Routing Protocol [MXS1]
36 XTP XTP [GXC]
37 DDP Datagram Delivery Protocol [WXC]
38 IDPR-CMTP IDPR Control Message Transport Proto [MXS1]
39 TP++ TP++ Transport Protocol [DXF]
40 IL IL Transport Protocol [Presotto]
41 IPv6 Ipv6 [Deering]
42 SDRP Source Demand Routing Protocol [DXE1]
43 IPv6-Route Routing Header for IPv6 [Deering]
44 IPv6-Frag Fragment Header for IPv6 [Deering]
45 IDRP Inter-Domain Routing Protocol [Hares]
46 RSVP Reservation Protocol [Braden]
47 GRE General Routing Encapsulation [Li]
48 DSR Dynamic Source Routing Protocol [RFC4728]
49 BNA BNA [Salamon]
50 ESP Encap Security Payload [RFC4303]
51 AH Authentication Header [RFC4302]
52 I-NLSP Integrated Net Layer Security TUBA [GLENN]
53 SWIPE IP with Encryption [JI6]
54 NARP NBMA Address Resolution Protocol [RFC1735]
55 MOBILE IP Mobility [Perkins]
56 TLSP Transport Layer Security Protocol [Oberg]
using Kryptonet key management
57 SKIP SKIP [Markson]
58 IPv6-ICMP ICMP for IPv6 [RFC1883]
59 IPv6-NoNxt No Next Header for IPv6 [RFC1883]
60 IPv6-Opts Destination Options for IPv6 [RFC1883]
61 any host internal protocol [IANA]
62 CFTP CFTP [CFTP][HCF2]
63 any local network [IANA]
64 SAT-EXPAK SATNET and Backroom EXPAK [SHB]
65 KRYPTOLAN Kryptolan [PXL1]
66 RVD MIT Remote Virtual Disk Protocol [MBG]
67 IPPC Internet Pluribus Packet Core [SHB]
68 any distributed file system [IANA]
69 SAT-MON SATNET Monitoring [SHB]
70 VISA VISA Protocol [GXT1]
71 IPCV Internet Packet Core Utility [SHB]
72 CPNX Computer Protocol Network Executive [DXM2]
73 CPHB Computer Protocol Heart Beat [DXM2]
74 WSN Wang Span Network [VXD]
75 PVP Packet Video Protocol [SC3]
76 BR-SAT-MON Backroom SATNET Monitoring [SHB]
77 SUN-ND SUN ND PROTOCOL-Temporary [WM3]
78 WB-MON WIDEBAND Monitoring [SHB]
79 WB-EXPAK WIDEBAND EXPAK [SHB]
80 ISO-IP ISO Internet Protocol [MTR]
81 VMTP VMTP [DRC3]
82 SECURE-VMTP SECURE-VMTP [DRC3]
83 VINES VINES [BXH]
84 TTP TTP [JXS]
85 NSFNET-IGP NSFNET-IGP [HWB]
86 DGP Dissimilar Gateway Protocol [DGP][ML109]
87 TCF TCF [GAL5]
88 EIGRP EIGRP [CISCO][GXS]
89 OSPFIGP OSPFIGP [RFC1583][JTM4]
90 Sprite-RPC Sprite RPC Protocol [SPRITE][BXW]
91 LARP Locus Address Resolution Protocol [BXH]
92 MTP Multicast Transport Protocol [SXA]
93 AX.25 AX.25 Frames [BK29]
94 IPIP IP-within-IP Encapsulation Protocol [JI6]
95 MICP Mobile Internetworking Control Pro. [JI6]
96 SCC-SP Semaphore Communications Sec. Pro. [HXH]
97 ETHERIP Ethernet-within-IP Encapsulation [RFC3378]
98 ENCAP Encapsulation Header [RFC1241,RXB3]
99 any private encryption scheme [IANA]
100 GMTP GMTP [RXB5]
101 IFMP Ipsilon Flow Management Protocol [Hinden]
102 PNNI PNNI over IP [Callon]
103 PIM Protocol Independent Multicast [Farinacci]
104 ARIS ARIS [Feldman]
105 SCPS SCPS [Durst]
106 QNX QNX [Hunter]
107 A/N Active Networks [Braden]
108 IPComp IP Payload Compression Protocol [RFC2393]
109 SNP Sitara Networks Protocol [Sridhar]
110 Compaq-Peer Compaq Peer Protocol [Volpe]
111 IPX-in-IP IPX in IP [Lee]
112 VRRP Virtual Router Redundancy Protocol [RFC3768]
113 PGM PGM Reliable Transport Protocol [Speakman]
114 any 0-hop protocol [IANA]
115 L2TP Layer Two Tunneling Protocol [Aboba]
116 DDX D-II Data Exchange (DDX) [Worley]
117 IATP Interactive Agent Transfer Protocol [Murphy]
118 STP Schedule Transfer Protocol [JMP]
119 SRP SpectraLink Radio Protocol [Hamilton]
120 UTI UTI [Lothberg]
121 SMP Simple Message Protocol [Ekblad]
122 SM SM [Crowcroft]
123 PTP Performance Transparency Protocol [Welzl]
124 ISIS over IPv4 [Przygienda]
125 FIRE [Partridge]
126 CRTP Combat Radio Transport Protocol [Sautter]
127 CRUDP Combat Radio User Datagram [Sautter]
128 SSCOPMCE [Waber]
129 IPLT [Hollbach]
130 SPS Secure Packet Shield [McIntosh]
131 PIPE Private IP Encapsulation within IP [Petri]
132 SCTP Stream Control Transmission Protocol [Stewart]
133 FC Fibre Channel [Rajagopal]
134 RSVP-E2E-IGNORE [RFC3175]
135 Mobility Header [RFC3775]
136 UDPLite [RFC3828]
137 MPLS-in-IP [RFC4023]
138 manet MANET Protocols [RFC5498]
139 HIP Host Identity Protocol [RFC5201]
140 Shim6 Shim6 Protocol [RFC5533]
141-252 Unassigned [IANA]
253 Use for experimentation and testing [RFC3692]
254 Use for experimentation and testing [RFC3692]
255 Reserved [IANA]
Posted in Real World, Routing & Switching Lab | Leave a Comment »
ipv6 cef – For Unicast RPF to work, Cisco Express Forwarding must be configured globally in the router
Posted by Peter Kurdziel on July 8, 2009
The following prerequisites apply to Cisco Express Forwarding and distributed Cisco Express Forwarding for IPv6: – To forward IPv6 traffic using Cisco Express Forwarding or distributed Cisco Express Forwarding, you must configure forwarding of IPv6 unicast datagrams globally on the router by using the ipv6 unicast-routing command, and you must configure an IPv6 address on an interface by using the ipv6 address command.
– You must enable Cisco Express Forwarding for IPv4 globally on the router by using the ip cef command before enabling Cisco Express Forwarding for IPv6 globally on the router by using the ipv6 cef command.
– To use Unicast Reverse Path Forwarding (RPF), enable Cisco Express Forwarding switching or distributed Cisco Express Forwarding switching in the router. There is no need to configure the input interface for Cisco Express Forwarding switching. As long as Cisco Express Forwarding is running on the router, individual interfaces can be configured with other switching modes.
Note For Unicast RPF to work, Cisco Express Forwarding must be configured globally in the router. Unicast RPF will not work without Cisco Express Forwarding.
Posted in IPV6, Routing & Switching Lab | Leave a Comment »
TEN TIPS FOR TAKING THE LAB EXAM
Posted by Peter Kurdziel on July 8, 2009
TEN TIPS FOR TAKING THE LAB EXAM
| 1 | Read the entire exam first and check for addressing issues. Do not skip any details or sections. |
| 2 | Manage your time. Make a plan to cover all the sections in the time provided. Work out how much time you will spend on each section, keeping in mind the point value of the questions. Don’t forget to allow time at the end to verify your solutions. |
| 3 | Clarify the requirements of each question. Don’t assume requirements that aren’t mentioned in the question. During the lab, if you are in any doubt, verify your understanding of the question with the proctor. |
| 4 | Do each question as a unit. Configure and verify before moving to the next question. You may want to redraw the topology with all the details available. This will help you visualize and map the network. |
| 5 | Troubleshoot. You must know how to troubleshoot using the tools available. Although troubleshooting is important, don’t lose too much time working on a 2- or 3-point question. If you’re caught off-guard by an unfamiliar topic, don’t let it absorb too much time. Work on the things you are more comfortable with and go back to difficult items later. |
| 6 | Keep a list. During the exam, make notes on configurations and settings as you move through the exam. Make a separate list for items you have not been able to address or where you have not achieved the desired result which you’ll need to revisit. |
| 7 | Test your work. Never rely on a configuration done in the early hours of the exam. There is a possibility that an item you configured a few sections earlier can become broken and non-functional. Keep in mind that points are awarded for working configuration only. |
| 8 | Save your configurations often. |
| 9 | Don’t make any drastic changes in the last half hour of the exam. |
| 10 | Speed is vital on the exam. Review and practice core material the week before the exam to ensure you can move quickly through the less challenging questions. |
Posted in Routing & Switching Lab | Leave a Comment »
