Null entry in "sh ip route"

Hi All,
why am I getting the below, a null entry for 192.168.169.0.?
Roger#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
192.168.169.0/24 is variably subnetted, 2 subnets, 2 masks
D 192.168.169.0/24 is a summary, 00:03:25, Null0
C 192.168.169.0/30 is directly connected, FastEthernet0/0
Here is sh run
Roger#sh run
Building configuration...
Current configuration:
version 12.0
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
hostname Roger
enable secret xxxx
enable password regor
ip subnet-zero
ip host tom 192.168.169.1
process-max-time 200
interface FastEthernet0/0
ip address 192.168.169.2 255.255.255.252
no ip directed-broadcast
speed 100
full-duplex
interface FastEthernet0/0.110
no ip directed-broadcast
interface FastEthernet0/1
ip address 192.168.168.1 255.255.255.0
no ip directed-broadcast
router eigrp 1
network 192.168.168.0
network 192.168.169.0
ip classless
no ip http server
line con 0
transport input none
line aux 0
line vty 0 4
password 1234
login
no scheduler allocate
end
Roger#
This is just a study device at home. 2 2600s connected via crossover and a switch on either router(1900 and 2900).
Cheers.
coolboarderguy...

Hi All,
the 2nd router, Tom, is showing similar.
Tom#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.167.0/24 is directly connected, FastEthernet0/1
192.168.169.0/24 is variably subnetted, 2 subnets, 2 masks
D 192.168.169.0/24 is a summary, 00:00:10, Null0
C 192.168.169.0/30 is directly connected, FastEthernet0/0
Tom#
and the sh run
Tom#sh run
Building configuration...
Current configuration:
version 12.0
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
hostname Tom
enable secret 5 $1$pwJW$eRCDshGxVapccQPG8oG2U/
ip subnet-zero
ip host roger 192.168.169.2
process-max-time 200
interface FastEthernet0/0
ip address 192.168.169.1 255.255.255.252
no ip directed-broadcast
speed 100
full-duplex
interface FastEthernet0/1
ip address 192.168.167.1 255.255.255.0
no ip directed-broadcast
router eigrp 1
network 192.168.167.0
network 192.168.169.0
ip classless
no ip http server
line con 0
transport input none
line aux 0
line vty 0 4
password 1234
login
end
Tom#
Cheers.
coolboarderguy...

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I think that in this case that article is not what's required Shay as the question related to a "No Null" entry. The answer would be to add it into the list that is used to populate the list in the first place - generally by adding a "union select from dual" to the query that generates the list values.

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Do not accept Null entry in a Query

I have this query that searches for an string within the description field and would like not to accept an empty entry, is there some code I can put to do this?
Here is the query;
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JDBC MS Access--- cannot extract entry with null value with data type Meta

I'm trying to extract a data entry with null value by using JDBC. The database is MS Access.
The question is how to extract null entry with data type memo? The following code works when the label has data type Text, but it throws sqlException when the data type is memo.
Any advice will be appreciated! thanks!
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The question is how to extract null entry with data type memo?Okay, what you need to do is this:
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Advertise implicit-null label for static routes

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[wiki][proposal] Rewrite of the "Router" wiki entry

This is a proposal to establish rewrite and restructure the entire "Router" wiki article located at http://wiki.archlinux.org/index.php/NAT … connection (The wiki entry "Router" currently redirects here).
There has been much discussion of a rewrite in the #archlinux irc channel and a small number of users, including myself, wish to heavily rewrite and reorganize the information located at http://wiki.archlinux.org/index.php/NAT … connection and http://wiki.archlinux.org/index.php/NAT … d_features.
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The rewritten entries would be divided into the following wiki entries - Router: Basic (redirected from "Router"), Router: Advanced.
The rewritten entries would contain similar information to the original entries, however with some sections removed, reorganized or relocated and easier to follow. This would be able to ensure accessibility and usability of the Router entry for novice users, and at the same time allow more advanced users to additionally tweak their router.
Due to the large amount of information provided by both existing entries, a third "Draft" entry would be proposed - Router: Draft.
This would be a public wiki entry where those who wish to contribute to the rewrite of these articles can join and provide feedback to the existing status of the rewrite project. This would allow the information currently present on the existing pages to still be usable while the rewrite is taking place. Once the draft has been deemed usable enough to replace the existing entries, the draft page will be removed and the existing entries will be replaced by the newly rewritten router entries.
Note: It came to my attention that it may just be wiser creating the Router: Basic and Router: Advanced pages and doing the rewrite on each respective page instead. During the time of the rewrite, an "article in progress" notice can be displayed informing users that the article itself may not be ready and should be followed at their own risk. As it stands, Router: Draft will be unnecessary.
Those of us who are adament about rewriting these entries are curious to hear the community response to this proposal. We are going to begin rewriting the entries very soon and would like others to contribute or review our works on a regular basis. Please let us know what you think, as we would like to hear the community suggestions and insight on this proposal.
Last edited by roadmap (2009-04-14 10:36:42)

u_no_hu wrote:
@roadmap..
Nice work guys...
One suggestion... dont include unnecessary(ie details available on other parts of wiki) details...
IMO you can nuke this whole part without any loss of content because anybody who is going to install arch on a router will already be familiar with pacman and upgrading etc.
On a default installation, Arch Linux does not come with what you will need to configure an Arch Linux router. You will need to install some additional packages to make Arch Linux function how we intend to. For this task, we will be using the package manager pacman.
Tip: If you want more information on pacman and its uses, please see the Pacman wiki page
[edit] Upgrading Your Packages
If you have not done so already, you should go ahead and update your installation to the latest packages. You can do this by running the following command from the command line.
pacman -Syu
Allow it to proceed and once it has finished, continue to the next part of this tutorial.
This is just my opinion and people may differ, but i find lot of wiki pages (xorg/beginners guide to mention two) to be bloated with excess info instead of linking to relevant part of wiki.
I have thought about your inquiry and my response is hard to put it in perspective. I do agree with your philosophy about the fact that the specific section is unnecessary. However, those who may be attempting to setup an Arch Router may not have any internet access, outside of the Arch Router machine itself, at the time they are following the tutorial.
You have to remember that this is a tutorial/howto, and a good tutorial should contain all information necessary to complete the desired task. If someone should desire more information about a particular application or have a differing situation to the one that the tutorial is trying to achieve, then linking them to more information about each application may provide additional help to their situation.
That was one of my complaints with the previous Router entry: it would send you off site to find one or two lines of config that could have just very well been included into the original article. It expected you to have full internet access while telling you flat out to tear apart your network in the process, and by doing so destroyed parts of its usability.
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Implicit null

hai experts,
just now stepped into mpls world.
i am refering the book "MPLS Fundamentals" by Luc De Ghein.
In the implicit null portion the author states that " PHP is the default mode in cisco IOS.In case of ipv4 over mpls ,cisco ios only advertise the implicit null label for directly connected routes and summarized routes."
but some of them told me that it will send implicit null for all routes it learns.
Which is true or is there any hidden meaning in connected and summarized routes???

Hi,
If the question is about IPv4 routes learned in a VRF, then implicit-null will not be used at all - neither for PE directly connected nor for summary routes. The reason is that a PE needs a VPN label to identify the VRF context, because the IP destination address alone can not do it as you might have overlapping IP addresses in different VRFs. If you have a look at the labels in a VRF (show mpls forwarding-table vrf ...) you will see "Aggregate" for VRF connected or VRF summary routes. This denotes, that the PE will use the VPN label to select the proper VRF context and then has to perform an additional IP lookup to figure out, who should get the packet. If a label is for a VRF connected network the IP packet could be for the PE or the CE sharing this network. A VPN label alone in this case will not be enough, a double lookup is needed.
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Implicit & Explicit Null Labels

Hi..
I am a bit confused in Implicit and Explicit null labels. The RFC Says as follows :
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and the forwarding of the packet must then be based on the IPv4 header.
EXPLICIT NULL LABEL : This is a label that an LSR may assign and distribute, but which never actually appears in the encapsulation. When an LSR would otherwise replace the label at the top of the stack with a new label, but the new label is "Implicit NULL", the LSR will pop the stack instead of doing the
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My question is, which one is used in PHP operation. Consider I have a scenario like this :
CE1--PE1---P---PE2---CE2
How do I make the P router as the PHP router in this case???I need to have a implicit null label set on P router????
What about explicit null label then???
Regards,
RAJ

by defaulf, the P router will use implicit null label. For you to use the explicit null label, use the command
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The explicit null label is often useful in QoS implementation scenarios.
See the following url
http://www.cisco.com/en/US/products/ps6350/products_command_reference_chapter09186a0080430c63.html#wp1020450

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I am not getting why its is throwing null pointer exception.Kindly advise
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Hi
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Hi,
I get the same exception while reading a ZIP file. The size if the ZIP file is just 82KB but I am reading it over FTP not sure if it makes any difference. I am using JDK 1.4.2_05. Here is the code I am trying to execute.
public class TestFTP {
public static void main( String[] argv ) throws Exception {
String inboundPath = "/transfer/inbound/";
FTPClient ftp = new FTPClient();
ftp.connect("123");
ftp.login( "123", "123" );
ftp.changeWorkingDirectory(inboundPath);
FTPFile[] zipFiles = ftp.listFiles("*.zip");
TelnetClient telnetClient;
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JavaFX's null not allowed is a thorn in my side....

Hi All,
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Rule: JavaFX's sequences can't contain null entries.
Further more, I could say "Nope, I don't have a value/update yet so I will just use an object placeholder/wrapper with null assignment". In my case, JavaFX object's are multiple and ordered. Perfect for a sequence! Except, you can't store null in a sequence! Thus, if you are looking for a team's sport's top batsman.. the 3rd batsman and they don't exist yet.. then 'team[2] = null' wont insert! So how can I find and bind to the 3rd batsman? We'll either I avoid sequences, which means native array's or java collections... but then I can't really bind to them! Or, everytime the sequence changes I need to search/iterate over the entire sequence to determine if there is a 3rd batsman in the sequence (and that won't necessarily be the 3rd entry).
Both these 'null not allowed' rules cause significant problems and have huge flow on effects onto the code that uses them. I believe this is totally wrong and a bad feature of the language and completely contradicts autoboxing! The identification of a data type reference being null is extremely significant. It is the responsibility of the receiver of a null reference/argument to decided how they want to handle the null reference (see autoboxing nullpointer exceptions if you don't believe me and reasons not to use java primitives). Removing the ability for this to occur is a step backwards for functional programming. I know you will say that I could just use the java.lang.*, a fair claim... but don't forget this means more work! The very reason you might be considering JavaFX in the first place.
Anyway my rant is over, I really love JavaFX.... just not these x2 rules.

The technique PhiLho refers to is often called the "null object pattern". If done properly it needn't be hackish at all, and indeed it can simplify a lot of processing code. Even if the "primitive" values (Number, String, etc.) could be null, and even if you could put nulls into a sequence, you're probably better off putting in an actual object that represents the absence of a value. The reason is that when you go to process that data, instead of just processing it, you have to put in checks for nulls here and there, and do special-case processing for it.
Consider displaying a list of, say, the top five batsmen. You'll want to have a sequence of five batsmen, and you'll want to put five CustomNodes or something into a VBox to display the names, statistics, etc., something like the following:
VBox {
    content: [
        for (b in [0..<5]) {
            BatsmanNode {
                name: bind batsmen.name
innings: bind batsmen[i].innings
notOuts: bind batsmen[i].notOuts
visible: bind batsmen[i].valid
You can't do this if there were a null in the sequence, even if it were allowed. Instead, you should put a "fake" batsman object into the sequence, and make its "valid" variable be false. This way the corresponding BatsmanNode will be invisible. Or, you could have it display "(no entry)" in grey text, or something like that.
The point is that if you always have a real object there, even if it represents a "null" or the absence of a value, it removes special-case processing code and enables you to do things like bind to it.

Null entry in "sh ip route"

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