Juniper Training.

During my training at Juniper last week I found these important document resources. I felt that these will be useful for all and sending across. The training basically covered all the topics for JNCIA-M. The training was great. Now I feel very comfortable with Junos configurations. Obviously I should keep using what I learnt there :)

JNCIA-M Study Guide:
You can download all the study guides from Juniper for free. Herewith I am attaching the link for JNCIA study Guide. I am motivated to take this exam.
http://www.juniper.net/training/certification/JNCIA_studyguide.pdf

Juniper Technical documents:
This link has all Juniper technical documentation. It will be worth to book mark.
http://www.juniper.net/techpubs/

Junos to IOS command reference:
I thought I need to make a list of equivalent commands in Junos to IOS, but they have it already on their website. You can download that from the following link.
https://www.juniper.net/customers/csc/documentation/techdocs/downloads/pdf/350023.pdf

Juniper router simulators:
Not but least. The following links explain how to simulate Juniper router on your PC. The simulator will help you in practicing the commands and other features.
http://www.smogey.net/tech/Juniper/Olive/index.htm#credit
http://brokenpipes.blogspot.com/2008/01/olive-is-alive.html

Please let me know if you have any questions.

Thank you.

Junos Documentation.

JNCIA Study Guide can be downloaded from:

http://www.juniper.net/training/certification/JNCIA_studyguide.pdf

Juniper Technical Documentation can be found at:

http://www.juniper.net/techpubs/

Mapping of basic Junos commands to IOS commands

https://www.juniper.net/customers/csc/documentation/techdocs/downloads/pdf/350023.pdf

IP Fast Switching, Process Switch and CEF Switching.

I found nice information on Fast Switching, Process Switch and CEF Switching in the following link.

 

http://ciscogeek.wordpress.com/2008/10/14/ip-switching-fast-switching-process-switching-cef-switching/

 

 

Cisco Express Forwarding vs Fast Switching:

Cisco Express Forwarding vs Fast Switching:

 

Enabling CEF may be a method to alleviate the increased traffic load . CEF is supported in IOS releases 11.1( )CC, 12.0, and later on the Cisco 7200/7500/GSR platforms. Support for CEF on other platforms may be in IOS release 12.0 or later. You can investigate further with the Software Advisor tool on CCO.

 

It may not be possible to enable CEF on all routers for one of the following reasons:

 

--Insufficient memory

 

--Unsupported platform architectures

 

--Unsupported interface encapsulations
 
Fast Switching Behavior and Implications:
 
The following are implications of using fast switching:

 

--Traffic driven cache, or the cache is empty until the router switches packets and populates the cache.

 

--First packet is process switched (since cache is initially empty).

 

--Cache built at a granularity of the most specific Routing Information Base (RIB) entry part of a major net (if RIB has /24s for major net 131.108.0.0, the cache is built with /24s for this major network).

 

--/32 caching for load balancing - per destination load-balancing only (when load balancing, cache is built with /32s for that major net).

 

Note: These last two issues can potentially cause a huge cache that would consume all memory.

 

--With default route, caching is done at major network boundaries.

 

The Cache Ager runs every minute and checks 1/20th (5 percent) of the cache for unused entries under normal memory conditions, and 1/4th (25 percent) of the cache in a low memory condition (200k).
The command to change the above values is: ip cache-ager-interval X Y Z, where:

 

X is <0-2147483> number of seconds between ager runs, default = 60 seconds.

 

Y is <2-50> 1/(Y+1) of cache to age per run (low memory), default = 4.

 

Z is <3-100> 1/(Z+1) of cache to age per run (normal), default = 20.

 

CEF Advantages:

--The Forwarding Information Base (FIB) table is built based on the routing table, therefore forwarding information exists before the first packet is forwarded. The FIB also contains /32 entries for directly connected LAN hosts.

 

--The Adjacency (ADJ) table contains the Layer 2 rewrite information for next-hops and directly connected hosts (an ARP entry creates a CEF adjacency).

 

--There is no cache ager concept with CEF to spike CPU utilization. A FIB entry is deleted if a routing table entry is deleted.

 

--There is a more efficient lookup with CEF (maximum of 4 lookups).

 

Caution: Again, a default route pointing to a broadcast or multipoint interface means that the router will ARP for every new destination, potentially creating a huge adjacency table until the router runs out of memory. If CEF fails to allocate memory CEF/DECF will disable itself and will have to be manually re-enabled.