Monday 7 January 2013

Route Precedence

Few days back one of my friend ask me, if we have three routes

10.10.10.0/24 via bgp
10.10.10.0/24 via ospf
10.10.0.0/16 via eigrp

which route will take for 10.10.10.1??

Then I start searching  the  answers on net and luckily find a solution.  

Now the basic funda is,

Route selection precedence is as follows

1. Most Specific route
2. AD value
3. Metric


Now here most specific routes are

10.10.10.0/24 via bgp
10.10.10.0/24 via ospf

Now AD value will come in the picture as tie breaker....

Take a look at the following Table for AD values

Default Administrative Distances
Connected 0
Static 1
eBGP 20
EIGRP (internal) 90
IGRP 100
OSPF 110
IS-IS 115
RIP 120
EIGRP (external) 170
iBGP 200
EIGRP summary route 5


Now the Answer is a question, Which BGP route was that, EBGP or IBGP??

If it is IBGP (AD value: 200), OSPF routes will get precedence…. Else it gonna take BGP routes (AD Value: 20)

Internet Explorer : Error Codes - Explained

52 Runtime Error

This is a "bad file name or number" error in JavaScript.

It means that the script cannot find a file it is looking for (web-page, course component) and is most likely a connectivity problem.

Try to clear your temporary internet files which should resolve any further problems... If this does not then speak with the website administrator as there may be a problem with the websites server.


400 Bad File Request

Usually means the syntax used in the url is incorrect (e.g. uppercase letter should be lowercase letter; wrong punctuation marks)


401 Unauthorised

The website server is looking for some encryption key(s) from the client (your computer) and is not getting it. Also, a wrong password may have been entered. Try it again, paying close attention to case sensitivity..


403 Forbidden/Access Denied

Similar to 401, special permission is needed to access the website A password and/or username may not be correctly registered on the websites database. Other times the website server may not have the proper permissions set up on its directories...


404 File Not Found

Server cannot find the file you requested. Refreshing the page (F5) should resolve this problem, although continued error messages may mean the page is no longer available, that there is considerable internet congestion (in which case the user should try again later).

Alternatively the file could have been either been moved or deleted, or you entered the wrong URL or document name. Look at the URL. If a word looks misspelled, correct it and try it again. If that doesn't work backtrack by deleting information between each backslash, until you come to a page on that site that isn't a 404.

From there you may be able to find the page you're looking for. This has to be the most common Internet Explorer Error message on the Internet!


408 Request Timeout

Client (your computer) stopped the request before the server finished retrieving it. A user will either hit the stop button, close the browser, or click on a link before the page loads. Usually occurs when servers are slow or file sizes are large.


500 Internal Error

Couldn't retrieve the HTML document because of server-configuration problems.

Contact website administrator...


501 Not Implemented

Web server doesn't support a requested feature.


502 Service Temporarily Overloaded

Server congestion; too many connections; high traffic. Keep trying until the page loads. This can be a common occurrence at peak news times eg. the Twin Towers during September 2001 brought CNN and the BBC news sites to a slow crawl and many folks got this error.


503 Service Unavailable

Server busy, site may have moved, or you lost your dial-up Internet connection!


Bad File Request

Browser may not support the form or other coding you're trying to access.


Connection Refused by Host

Either you do not have permission to access the site or your password is incorrect. Try again!


Errors on Page

This error message is a catch-all statement meaning there is something on the web page that the browser either hasn't read properly (connectivity problem) or there are missing items in the web page itself. This problem normally affects the graphics on a web page.

This can be a temporary glitch (caused by insufficient bandwidth), and may be quickly resolved, or it can have a more complex and longer term problem. With regard to most cases of this Internet Explorer Error message, it is due to not having given sufficient time to download the page you are requesting.

It is necessary to wait until the bottom left hand corner of the page reads 'done' before selecting any other links on the page to move forward.


Failed DNS Lookup

The Domain Name Server can't translate your domain request into a valid Internet address. The website server may be busy or down, or incorrect url (web address) was entered.


File Contains No Data

Page is there but is not showing anything. Error occurs in the document. Attributed to bad table formatting, or stripped header information....


Host Unavailable

Host server down. Hit reload or go to the site later


Network Connection Refused by the Server

The Web server is busy. To resolve this problem, refresh the page. (Press Ctrl and F5).


Runtime Error

(The information in this solution applies to: Internet Explorer 5.5 (SP1) 95 / 98 / 98 Second Edition / NT4.0 / 2000). When you attempt to browse to various websites, you may receive an error message similar to the following 'A runtime error has occurred. Do you wish to debug? Line number Error: Permission Denied.'

This can occur if you upgrade to IE 5.5 (SP1). The upgrade enables the script-debugging and script-error-notification options. (Note: Because there are several versions of Windows, the following steps may be different on your computer. If they are, please consult your product documentation to complete these steps:)

To resolve this issue, disable the script-debugging and script-error-notification options. To do this, follow these steps:

1. Start Internet Explorer.
2. On the Tools menu, click Internet Options.
3. Click the Advanced tab .
4. Click to select the Disable script debugging check box .
5. Click to clear the Display a notification about every script error check box .
6. Click Apply, and then click OK.
Fortunately this is a very rare Internet Explorer Error message...


Script Error

Script errors are caused when something goes wrong when surfing some web pages. It is caused by VBScript or JavaScript code that is embedded within certain web pages. These errors are mostly due to connectivity problems, though can occasionally be caused by browser incompatibilities. Ensure that you have a compatible browser version (IE 5.5 and above or Netscape 4.76 and above).


Unable to Locate Host

Host server is down, Internet connection is lost, or URL typed incorrectly.

If refreshing the page doesn't work, try clearing the Temporary Internet Files and History and refreshing again. You may have to wait until later.

How to Know Nokia Hardware - Model - Serial Number

FW [Admin]# cat /var/etc/.nvram
Vendor Nokia
Chassis serialnum: 93063100325
Model IP390
FW [Admin]#

Saturday 5 January 2013

Useful Netscreen Commands for Troubleshooting

Netscreen Commands for Troubleshooting:
Here is some useful Netscreen commands for troubleshooting.

get config : to get device configuration
save : to save changes to config
get system : gets system information, Netscreen mode
get session info : shows load on the firewall 85+ implies there will be some latency
get interface : shows interfaces, zones
get address trust/unturst: shows defined network objects
get Arp : shows firewall Arp entries
get route : shows firewall routes
get service : shows firewall services
get group address : network groups
get group service : service groups
get policy in/out : shows applied firewall policies
get log traffic : shows firewall logs – options: based on src/dst/IP/port
unset : to remove a config statement
get user all : shows vpn users
get log event : shows vpn logs
get MIP : shows one to one Nat’s
get VIP : shows configured port forwarding rules
get route ip x.x.x.x: finds the specific route for an ip
set policy id xx : put you in a specific policy then you can add more objects it instead of creating a group

Basic Netscreen Commands

Basic NETSCREEN Firewall Commands
If you are new to managing the Netscreen Firewall, then these commands will help you in managing the Netscreen Firewall from the Command Line Interface.

NETSCREEN
Note:Always remember to use the TAB when you are not sure the syntax of the command for a Netscreen Firewall. When you press TAB on your keyboard, it would give you what the next options are, and you can chose from the same. TAB is your best friend.

Step 1: define networks & network groups
***********************************************
Set address trust int-10.1.1.0_24 10.1.1.0/24
Set address untrust ext-192.168.15.15 192.168.15.15/32
Set group address untrust Remote
Set group address untrust Remote add ext-192.168.15.15

Step 2: define services & service groups
**********************************************
Set service tcp_445 protocol tcp src-port 1024-65535 dst-port 445-445 timeout 120
Set service tcp_3399 protocol tcp src-port 1024-65535 dst-port 3390-3390 timeout 120
Set group service outsrvgroup1
Set group service outsrvgroup1 add http
Set group service outsrvgroup1 add https

Step 3: Define policies
*************************
set policy from trust to untrust int-10.1.1.0_24 any outsrvgrp1 permit log count
Note: policies are applied from zone to zone.

Step 4: define NAT
**********************
NAPT is on by default.

Step 5: define one to one NAT (MIP)
*****************************************
Set interface untrust MIP 192.168.1.15 host 10.1.1.15 netmask 255.255.255.255
Set group service insrvgroup1
Set group service insrvgroup1 add http
Set group service insrvgroup1 add https
Set policy from untrust to trust any MIP(192.168.1.15) insrvgroup1 permit log count
Set policy move 59 before 4
(Move the new policy is before the default deny policy)

Step 6: define port forwarding (VIP)
*****************************************
Set interface untrust VIP 192.168.1.55 443 https 10.1.1.55
Set policy from untrust to trust any VIP::1 https permit log count

Step 7: define routes
************************
Set route 10.1.1.0/24 gateway 192.168.1.254

Friday 4 January 2013

Fortigate firewall demo free access. Also FortiManager and FortiAnalyzer

As someone said best things in life are free.

Here are links to the demo Forigate firewall, ForiAnalyzer and FortiManager open to access from anywhere . So that you can familiarize yourself with the Management GUI look and feel.


NOTE: Access is read-only.
NOTE 2: No , it is not me being so generous, it’s Fortinet caring for us.


Fortigate 300 :
user:demo
password: fortigate
fortigate.com


ForiAnalyzer 800:
user:demo
password: fortianalyzer
fortianalyzer.com 


FortiManager 400:
user:demo
password: fortimanager
fortimanager.com