22 Jul 2013

Basic Tivoli Storage Manager (TSM) Backup Client commands

Backup using TSM, useful link for the commands and procedures:

Using the TSM Client Command Line Interface for Backup & Restore







5 Apr 2013

6500 Performance monitoring

Here are some commands to see stats/performance.



#show fabric utilization detail
  Fabric utilization:     Ingress                    Egress
    Module  Chanl  Speed  rate  peak                 rate  peak              
    1       0        20G    0%   18% @21:45 06Jan13    0%   15% @09:55 07Jan13
    1       1        20G    3%   10% @02:17 10Feb13    1%   10% @18:21 20Jul12
    2       0        20G    0%   10% @12:43 01Apr13    1%   16% @13:49 27Jan12
    2       1        20G    0%   11% @02:02 08Feb13    0%   10% @12:14 14Sep12
    3       0        20G    0%    9% @15:30 15Feb13    0%   98% @15:10 27Sep12
    3       1        20G    0%    9% @23:02 02Jun12    0%   97% @15:10 27Sep12
    5       0        20G    1%   54% @15:04 27Sep12    3%   49% @15:10 27Sep12
    5       1        20G    0%    0%                   0%    0%              
    7       0        20G    0%    6% @10:21 17Aug12    0%   17% @01:08 20Sep12
    7       1        20G    0%   49% @15:10 27Sep12    0%   53% @15:04 27Sep12

#

6500 Fabric Troubleshooting

Switch Fabric- Troubleshooting tips




31 Dec 2012

Migrate to new Certificate Authority, while another one is in production

http://serverfault.com/questions/276342/adding-new-root-enterprise-ca-without-disturbing-existing-one

5 Dec 2012

OSPF packets

Intra-area - O
Inter-area - O IA (Summary routes)
External - O E2 or O E1

Preference order for destinations with multiple routes:
  1. Intra-area 
  2. Inter-area
  3. External E1 (external+internal cost)
  4. External E2 (only external cost)
LSA Types:

Type 1 (RL): Router Links.
Type 2 (NL): Network Links.
Type 3 (SL): Summary Links.
Type 4 : ASBR Summary Links.
Type 5 (EL): External Links.

17 Sept 2012

List largest folders (sorted)


du -sk * | sort -rn | while read size fname; do for unit in k M G T P E Z Y; do if [ $size -lt 1024 ]; then echo -e "${size}${unit}\t${fname}"; break; fi; size=$((size/1024)); done; done|more

27 Nov 2011

Microsoft NLB weirdness

NLB (Network Load Balancing) is a clustering tech. used by Microsoft products. There are two NLB methods:
  • Unicast NLB
  • Multicast NLB
NLB is a software clustering tech. and should be avoided. You are better off using Hardware load balancers such as Citrix Netscaler.

NLB has a bad design and using it causes switch flooding. The reason to this is it's ARP/MAC address usage.

To avoid problems where NLB must be used, check configuration examples for Cisco Devices. Catalyst Switches for Microsoft Network Load Balancing Configuration Example


Cisco Mobile to be in Istanbul in April

This is a chance to take the CCIE exams without traveling abroad.
Istanbul, Turkey Apr 16 - 20 R Routing & Switching, Security


Ref: Cisco Doc

23 Nov 2011

TwinGig Convertor configuration

These Cisco convertors are pretty handy I must say. It's an X2 Convertor module that is able to take 2 SFP modules; Allowing you to convert an X2 slot to twin SFP slots. Anyway, when you insert a TwinGig to a switch without first doing the pre-configuration, you're most likely to get an error like this:

%C4K_GLMMAN-3-X2PLUGGABLESEEPROMREADFAILED: Failed to read seeprom on port Te2/8. Reinsert X2 module or configure GigabitEthernet port group if TwinGigConverter is installed.

It's because the X2 slot you used is configured as a TenGig slot. It should be set to Gigabit for the TwinGig to be detected. The way it's done on an 4900M is:

hw-module module 2 port-group 4 select gigabitethernet

The catch is that the 8 port TenGig module used on the 4900M is over-subscribed and you will have to set a "port-group" which represents 2 ports, as "gigabit" to get the TwinGig to work.

After setting our port-group, the log will show the TwinGig is detected:

Nov 23 10:32:06.501: Port Te2/8: TwinGig Converter inserted: vendor: CISCO SYSTEMS, p/n: 800-27645-02, s/n: FDO14290SE5


Here are some references for more info:
Installation Notes for the Cisco TwinGig and OneX Converter Modules
Selecting X2/TwinGig Convertor Mode
SFP Interfaces of X2/Twin Gigabit Converter Do Not Come Up

27 Jun 2011

Protocol overhead

Various protocols introduce overhead to packet networks.
Good explanations here:
Protocol Overhead
Overhead in Packet Networks

20 Mar 2011

Fiber Optic Cable specs

Multi Mode

850nm and 1300nm
OM1: 62.5/125 µm
OM2: 50/125 µm
OM3: 50/125 µm Laser optimized. 10GbE for 300m (quality cables support 550m length)
OM4: Cable will support 125m links at 40 and 100 Gbit/s.


Single Mod
20km, 1 Gbps

13 Sept 2010

Get your GNS3 project fix

Here's a link to a great site from my friend Rene Molenaar:
GNS3Vault

Description from the site:

* Cool Scenarios to get the maximum out of your networking experience ;)
* Downloadable topologies that you can use right away with the GNS3 software.
* Different levels of difficulty, there's something for everyone...novice, intermediate and expert!
* The forum where you can discuss about all the labs.
* It's possible to review labs.
* You can share your labs with others.

AND Yes, all for free ;)

30 Jul 2010

Using 3rd Party SFP modules in Cisco Devices

All SFP modules contain in their EEPROM, a Serial Number, Vendor Name & ID, Security code and a CRC. The Switch checks this information, if it can't verify it might give messages like the following:
%PHY-4-UNSUPPORTED_TRANSCEIVER: Unsupported transceiver found in Gi1/0/1
%GBIC_SECURITY_CRYPT-4-VN_DATA_CRC_ERROR: GBIC in port 65538 has bad crc


There are two undocumented cisco commands to get 3rd party SFP modules to work:

switch(config)# service unsupported-transceiver
switch(config)# no errdisable detect cause gbic-invalid

16 Jun 2010

Upgrading Software on a 6509 Switch

Planning on upgrading the ancient CatOS 5.5(1)on our 6509 switch.

1. Check Supervisor NMP BootROM version. If Fw 5.1(1) then you must field upgrade your ROM. Check here.



Ref: Upgrading Software Images on Catalyst 6000/6500 Series Switches

15 May 2010

Running ASA and ASDM using GNS3/Qemu

Finally got ASA and ASDM to work nicely with GNS3.
Here's my setup:

GNS3 v0.7
Qemu (The one that comes with GNS3 v0.7)
ASA 802-k8 (files needed for Qemu are: asa802-k8.initrd.gz & asa802-k8.kernel)
ASDM 6.0(2)
Fiddler (Instructions to configure it are here)

To get ASDM to connect with ASA, you must use Fiddler to intercept the HTTPS stream and modify it to correct some of Qemu's shortcomings.
Then set your JRE to use fiddler as proxy.
All instructions can be found in the lengthy discussion at hacki.at. Make sure to read pages 17,18,+

9 May 2010

Visio tips & tricks

In this post I will collect Visio tips & tricks that I come up with and links to similar articles.

Shortcuts:
Ctrl+1 Pointer Tool
Ctrl+2 Text Tool
Ctrl+3 Connector Tool
Ctrl+W Zoom Whole Page
Ctrl+Shift+G Group
Ctrl+Shift+U Ungroup

Links:
Shortcuts to Edit in Visio @ Visio Insights
Nortel Visio Stencils
Visio Stencils collection (lots of vendors)

2 May 2010

STP, PVST, RSTP, MSTP articles

Many standards, many proprietary approaches.. All this causes interoperability and management headaches.

References:
Understanding MSTP, very in-depth article from Petr Lapukhov.
Understanding STP and RSTP Convergence, again by Petr.
Lots of valuable articles from ine blog.

1 May 2010

Cisco and HP Interoperability

Some pointers to related information on the net:

Articles:
Summaries from Dave Tucker's 3 Day Training: HP ProCurve/Cisco Interoperability – Day 1, Day 2, Day 3


Documents:
ProCurve and Cisco Spanning-tree Interoperability

Discovery Protocols, STP, Link Aggregation, IP Routing, etc:
HP & Cisco Interoperability Guide

20 Apr 2010

Troubleshooting High CPU Utilization

Cisco 7500 Series Routers, Troubleshooting TechNotes

* High CPU Utilization in Exec and Virtual Exec Processes

* The show processes Command

* Troubleshooting High CPU Utilization Due to Interrupts

* Troubleshooting High CPU Utilization due to Processes

* Troubleshooting High CPU Utilization in IP Input Process

* Troubleshooting High CPU Utilization on Cisco Routers

* Understanding VIP CPU Running at 99% and Rx-Side Buffering

* What Causes %SYS-3-CPUHOG Messages?

IOS Syslog facilities

Logging and debugging messages are the cornerstone of troubleshooting.

There are 4 possible destinations for Logging:
1.Console
2.Monitor
3.Buffer
4.Host
+plus SNMP

R1(config)#do sh logging
Syslog logging: enabled (9 messages dropped, 1 messages rate-limited, 0 flushes, 0 overruns, xml disabled)
Console logging: level debugging, 33 messages logged, xml disabled
Monitor logging: level debugging, 0 messages logged, xml disabled
Buffer logging: disabled, xml disabled
Logging Exception size (8192 bytes)
Count and timestamp logging messages: disabled
Trap logging: level informational, 38 message lines logged

Descriptions for the fields in the output above.

When troubleshooting in High CPU utilization situations, and you have to use debugging, make sure to disable or "level-limit" the console and monitor logging facilities. Instead use the buffered logging facility to record the debug output and view it with "show logging". This will allow the CPU to process the log messages in a high utilization environment.

To use a syslog server and set the log-level:

R1(config)# logging host
R1(config)# logging trap ?
<0-7> Logging severity level
alerts Immediate action needed (severity=1)
critical Critical conditions (severity=2)
debugging Debugging messages (severity=7)
emergencies System is unusable (severity=0)
errors Error conditions (severity=3)
informational Informational messages (severity=6)
notifications Normal but significant conditions (severity=5)
warnings Warning conditions (severity=4)

Reference:
Troubleshooting and Fault Management Commands @ Cisco
Troubleshooting High CPU Utilization on Cisco Routers @ Cisco

10 Apr 2010

Portable Product Sheets @ Cisco

Here's a page I came across on the Cisco Site.
Provides easy access to reference documents useful to partners.
Eg: Switch Performance, IOS Packaging, Router Memory/Performance, ISR Ref.Sheets, etc.

Portable Product Sheets

7 Apr 2010

Password recovery references for almost all Cisco Devices

Here's a great reference page from Cisco, explaining the pwd recovery procedures for many of their devices.

Password Recovery Procedures

Internet Map of Autonomous Systems in Türkiye

Here's a recent and very well done study of the Networks/ASs located in Türkiye, by Hakan Çetin.

Türkiye'nin Otonom Sistem Seviyesinde İnternet Haritasının Çıkarımı (TİH) - 2009


1 Apr 2010

Steps for migrating from PIX to ASA

You should be running v7.x on your PIX so that your configuration can be converted properly. Two ways of going about this:

* Tool-Assisted Conversion (Link)
* Manual Conversion

I'll covert the manual method here.
Upgrading your PIX to v7.x

1. Get copies of your config and version/license info
# show running
# write net
# show version


2a. If BIOS is earlier than 4.2, use Monitor Mode instead of copy tftp flash

Reboot and press BREAK or ESC during boot to enter Monitor Mode
monitor>interface
monitor>address
monitor>server
monitor>gateway
monitor>ping
monitor>file
monitor>tftp


PIX will automatically boot, but the software upgrade is only done in Memory, you MUST you go through the steps below to complete the upgrade!

2b. Upgrade System software

#enable
#copy tftp: flash:
Address or name of remote host []? 10.1.6.44
Source filename []? pix701.bin
Destination filename [pix701.bin]?


3. Now you have upgraded your software and your config was auto converted to v7.x
You should go through and check the changes made, which could be very different from your older pix config.

4. Use this config in your ASA appliance. Do this either with the Copy/Paste method, or via a tftp/ftp config file transfer.



Ref: Migration from PIX 500 Series Security Appliances to ASA 5500 Series Adaptive Security Appliances

30 Mar 2010

G.HSDSL Config through a Cisco 828 router

I'll copy this here for reference purposes. Used a few of these configs to connect one of my customers branch offices to their headquarters.

Be careful of the vpi/vci values which should be:
Point to point g.shdsl links: 0/35
Internet g.shdsl links: 8/35

!
controller DSL 0
mode atm
line-term cpe
line-mode 2-wire line-zero
dsl-mode shdsl symmetric annex B
line-rate auto
!

!
interface ATM0
no ip address
ip nat outside
ip virtual-reassembly
no atm ilmi-keepalive
!
interface ATM0.1 point-to-point
bandwidth 2048
ip nat outside
ip virtual-reassembly
pvc 8/35
pppoe-client dial-pool-number 1
!
!

!
interface Dialer0
mtu 1476
bandwidth 2048
ip address negotiated
ip nat outside
ip virtual-reassembly
encapsulation ppp
ip tcp header-compression iphc-format
ip tcp adjust-mss 800
load-interval 30
dialer pool 1
ppp authentication pap chap callin
ppp chap hostname user@isp
ppp chap password 0 123
ppp pap sent-username user@isp password 0 123
ppp ipcp dns request
ip rtp header-compression iphc-format
!

29 Mar 2010

Most useful Freeware/Shareware Windows Apps.

Firefox: THE browser of the Internet. Won't use anything else.
Total Commander, my choice of File Manager since, forever.
CDBurnerXP: Very nice CD/DVD/BlueRay, Data/Audio burner. Freeware.
SysInternals: Indispensable system tools.
Media Player Classic: With a few codecs, it's all you need to play your videos.
Winamp: Essential audio player for me.
TrueCrypt, an essential encryption suite.
BitComet, my choice of torrent client.
Foxit, a freeware PDF Reader. It's light-weight and fast, why use bloated Adobe apps?
Daemon Tools Lite, mount cd/dvd images
SyncToy
iMazingConverterWindows.exe iMazingConverter, heic'den jpg, mov'dan mp4'e çeviriyor, gerçekten free ama dikkat et, converter'ı indir sadece.

24 Mar 2010

Win7 Tips&Tricks, Useful Applications

* Shortcuts: Master List of Windows 7 Keyboard Shortcuts (Mar 09)
* Take ownership and delete files/folders for good!
For Files:
takeown /f file_name /d y
icacls file_name /grant administrators:F

For Directories (will perform action recursively):
takeown /f directory_name /r /d y
icacls directory_name /grant administrators:F /t

* Turn off Driver Signing
bcdedit.exe -set loadoptions DDISABLE_INTEGRITY_CHECKS
bcdedit.exe -set TESTSIGNING ON

* Turn off Hibernation
powercfg -h off

* Classic Start Menu and Explorer
Classic Shell, now this is very cool, I had enough of the new featureLESS Start menu and awkward Explorer

19 Mar 2010

CCNP at last!

Hooray!! Just became CCNP certified today.

Now it's onto my ultimate goal, CCIE Routing & Switching. Must start planning right away ;-)

11 Feb 2010

History of Computers and the Birth of the Internet

I've been reading "Where Wizards Stay Up Late" by Hafner&Lyon which tells the story of ARPA and how the network to connect all the different mainframes in universities came to being, which then would be the foundation of the Internet. It's written in a novel fashion and once you start flipping the pages it's hard to put it down!

There are mentions of many of the first huge computing machines that were built in various Universities and Corporations, such as the TX-2 in MIT Lincoln Labs, Q-32 that was transferred by the Airforce from SDC to ARPA, etc. So being the researcher I am :) I had to track these beasts and learn more about them. I shall write a separate article about these in the near future.

Computer History Museum in California (History Timeline)

10 Feb 2010

CCIE Preparation, devices to accumulate for a home lab

This is a WIP entry that I'll use to compile a list of useful devices/information for my future CCIE lab preperation

ISDN Simulator B-LinkU has 2 ports that you can connect to using U or S/T interface.

2520 Series Multiport routers, for use as Frame Relay switch, ISDN cloud.

6 Feb 2010

Cisco Router boot configuration

File Systems:
system: (RAM, where running-config is kept)
nvram: (NVRAM, where startup-config is saved)
bootflash: (Internal Flash memory)
slot0: (First PCMCIA slot)
slot1: (Second PCMCIA slot)

Copying:
#copy ftp: system:running-config
#copy ncp: system:running-config
#copy tftp: system:running-config

#copy ftp: nvram:startup-config
#copy rcp: nvram:startup-config
#copy tftp: nvram:startup-config

#copy system:running-config nvram:startup-config

Booting:

#show bootvar (verify the contents of the CONFIG_FILE environment variable.)
#boot config dest-flash-url (Set the CONFIG_FILE environment variable.)

#boot network ftp:[[[//[username[:password]@]location]/directory]
/filename]
#boot network rcp:[[[//[username@]location]/directory]/filename]
#boot network tftp:[[[//location]/directory]/filename]
#service config (Enable the router to download config-files at startup)

#boot system

Other Useful commands:
#service compress-config
#boot buffersize bytes (The buffer that holds the configuration file is usually the size of NVRAM. Larger configurations need larger buffers. )
(config)#config-register value
#dir [flash-filesystem:]

Examples
#copy system:running-config tftp://172.16.1.130/istanbul-config
#copy system:running-config ftp://netadmin1:mypass@172.16.101.101/Ankara-config
#copy rcp://netadmin1@172.16.101.101/host1-confg system:running-config
#copy slot0:4:ios-upgrade-1 nvram:startup-config


Ref: Rebooting and Reloading - Configuring Image Loading Characteristics @ Cisco
Cisco IOS Conf. Fundamentals Command Reference Boot Commands

1 Feb 2010

GRE over IPsec in a Hub-Spoke Topology w/ EIGRP (Lab) #2

Ok this is the enhanced version of the previous GRE lab I've posted.
We've decided to encrypt and secure all communications between our HQ and Branches.
As previously noted we needed GRE to run a dynamic routing protocol (EIGRP) between our networks. So here we implement an IPsec GRE tunnel that will encrypt all traffic including the multicast EIGRP messaging.

Download
Project files for GNS3.

30 Jan 2010

GRE Tunnels in a Hub-Spoke Topology w/ EIGRP (Lab) #1



Our company DasBoot Corp. has opened a few offices in Turkey.
The corporate offices are in sunny Izmir and there is one branch in Istanbul, and two in Ankara.

They all have basic Internet connectivity to our trusted ISP: DynamiteBBS. Which by the way is running IS-IS in its backbone with MPLS on top.

As the Network engineer of DasBoot, we decide to create tunnels in a hub-spoke fashion, connecting our branches to the corporate network. We use private addressing in our network (eg. 172.16.0.0). Here's a demonstration of running EIGRP to facilitate full connectivity between our networks. I know not too complicated but good practice and extensible lab anyways. Enjoy..
(Download GNS3 Project files)

My favorite Firefox addons

My browser of choice has been Firefox since the beginning, the 1.0 version in 2004. Before that I had been a longtime user of Opera.
I've been happily using the 3.5 version for a while and here are my favorite addons:

NoScript: It's a must have security addon IMHO.
Session Manager: A successful session manager. Very reliable and uses light resources.
Secure Login: Keeps track of my passwords for Forums/other sites that have low security priority on my list. I try to use different credentials for most sites.
oldbar: Brings back the Old Address Bar from version 2.
gspace: Use your gmail account space as a file cabinet.

29 Jan 2010

ISCW in the bag

I'm almost there, one to go!
Been reading up on ONT for a while, so this should be quick.

27 Jan 2010

Cisco Type 5 and Type 7 passwords

Cisco uses two types of password encryption to store your passwords. Type 7 is the Cisco proprietary method (Vigenere cypher) and is weak. The Type5 is encrypted using MD5 hashing, and is considered pretty strong. The "enable secret" password is stored using Type 5.

One can easily crack the Type7 passwords w/ utilities that are available on the net.
You can also do it straight from inside the IOS. Just create a key chain, and copy paste the encrypted string to the "key-string 7". Here's how:

24 Jan 2010

GRE Tunnel w/ IPsec protection, (and ISAKMP association using RSA keys)



1. Generate an RSA Public Key for our router.
#crypto key generate rsa general-keys label R1

Here you can see the generated key. Do the above for also R2, and copy paste their public keys to each other in next step.
#sh crypto key mypubkey rsa
% Key pair was generated at: 12:35:34 UTC Jan 24 2010
Key name: R1
Usage: General Purpose Key
Key is not exportable.
Key Data:
305C300D 06092A86 4886F70D 01010105 00034B00 30480241 00D35594 62FB3925
22EBD28E A64B12A7 2D0D44C1 DD28F9BF 8BA52834 516FC231 F1791352 A90ADEE0
A61E77C7 5F132B9E 11193B08 B338D531 D40EE40D 9699E742 DF020301 0001
% Key pair was generated at: 13:35:36 UTC Jan 24 2010
Key name: R1.server
Usage: Encryption Key
Key is not exportable.
Key Data:
307C300D 06092A86 4886F70D 01010105 00036B00 30680261 00A4764D E3D85AFD
2E9254C0 DBB88E08 CE86FA63 8D82C08C D11F14DF AF9264C9 2F5C1CBC 7081C66D
DFE73BB3 66E5A354 48B73EF0 3773545B F5BACBA7 CEBA55DA 4D3D52A1 0B62BFFD
BA93A21E 9B65D23F 9A843994 FAAEB67E BF565A6F 38A8DC3A D5020301 0001

2. Create a key chain. Addressed to router R2 with its IP address and copy paste its public key in here.
#crypto key pubkey-chain rsa
addressed-key 10.1.1.6
key-string
Enter a public key as a hexidecimal number ....
(PASTE HERE)
and use quit to finish


Download project files for GNS3

22 Jan 2010

IPsec VPN Lab, (using Dynamic crypto Map)



In this lab we connect the 3 sites of our company using secure IPsec VPN connections.

The ISP network consists of 4 Routers which are running EIGRP between them.

Our headquarters is connected to the ISP with the CE_4 router.
The branch offices, CE_5 being Branch1, and CE_8 Branch2.

Networks are 192.168.0.0/21 behing CE_4, edge router.
In Branch 1 we have 192.168.16.0/20 networks. (Simulated with loopback int)
In Branch 2 there are the 192.168.8.0/21 networks.

This setup demonstrates all the IPsec negotiation and tunnel establishment using a dynamic map on CE_4.. The key point is the create the relationship between the static crypto map and the dynamic one.

Due to our ISAKMP Policy we are using a Pre-Shared key for authentication. Which will be defined as a wildcard, so our VPN peers can connect using whichever address they have.

# crypto isakmp key address 0.0.0.0

Here are the lab files for gns3. Download

Good Reading:
Wildcard Pre-Shared Key Enhancement @cisco
Security Commands: crypto dynamic-map through ctype @cisco

21 Jan 2010

IPSEC VPN session status

Status of VPN Sessions

IKE SA

IPsec SAs

VPN Tunnel Status

Exists, active

Exists (flow exists)

UP-ACTIVE

Exists, active

None (flow exists)

UP-IDLE

Exists, active

None (no flow exists)

UP-IDLE

Exists, inactive

Exists (flow exists)

UP-NO-IKE

Exists, inactive

None (flow exists)

DOWN-NEGOTIATING

Exists, inactive

None (no flow)

DOWN-NEGOTIATING

None

Exists (flow exists)

UP-NO-IKE

None

None (flow exists)

DOWN

None

None (no flow exists)

DOWN


SDM Hints

I was using Firefox 3.5.1 and jre 1.6.12 (java6 update 12), some of the wizards were not launching. For example the Site-to-Site VPN and GRE Tunnel wizards.

I downgraded the my JavaVM to jre 1.6.0.3 and now all is working fine.

For documentation, requirements and installations goto SDM@cisco

To connect to your router via SDM:

#ip http server
#ip http secure-server
#ip http authentication local
#username privilege 15 password 0