Troubleshooting a network

oli356

oli356

oli356

Soldato
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Hey all

Might as well see if I can get any help here. Doing a CCNA troubleshooting excercise on packet tracer.

RsF2c.png

So above is what I have.

The wireless network can ping the other 2 network hosts.
The other 2 networks can ping each other but not the laptops. They can't ping 192.168.4.1 but can ping 192.168.3.1.

This is where I get confused, why can the laptop ping the deskstops but not the other way around.

ISR config internet settings (static):
Default gateway: 192.168.3.1
IP: 192.168.3.2

LAN Settings:
192.168.4.1

Router2 settings (centre router):
FastEthernet: IP 192.168.1.1
Ethernet 1/0: IP 192.168.2.1
Ethernet 1/0: IP 192.168.3.1

What I don't quite get exactly is the internet and LAN settings on the ISR and I assume that this is causing the problem... :S

Any help would be much appreciated :D
 
you definitely getting a ping reply not a destination unreachable response? because ping is a two way communication - it doesn't work unless there's routing in both directions. With that in mind you shouldn't be able to ping in only one direction.

if you could ping some hosts but not others on the same network you'd be looking at subnet masking errors.

It would also help my whiskey powered analysis if there were some subnet masks listed.
 
The requests are timing out when pinging from a desktop to a laptop. Fine the other way round. Which as you said, I don't understand..

Hmm, all the subnet masks for the desktops/laptops are 255.255.255.0 (as I would expect from Cisco, especially as at this stage subnetting hasn't been mentioned)

The only other thing I noticed is in router 2
Routing, static:
192.168.4.0/24 via 192.168.3.0

RIP routing
192.168.1.0
192.168.2.0
192.168.3.0

Which means nothing to me!

Thanks
 
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From:
IP Address......................: 192.168.1.2
Subnet Mask.....................: 255.255.255.0
Default Gateway.................: 192.168.1.1
Code: 
PC>tracert 192.168.4.101

Tracing route to 192.168.4.101 over a maximum of 30 hops: 

  1   7 ms      5 ms      9 ms      192.168.1.1
  2   *         *         *         Request timed out.
  3   *         *         *         Request timed out.
  4   *         *         *         Request timed out.
  5   *         *         *         Request timed out.
  6   *         *         *         Request timed out.
  7   *         *         *         Request timed out.
  8   *         *         *         Request timed out.
Wasn't going anywhere.

From:
IP Address......................: 192.168.2.2
Subnet Mask.....................: 255.255.255.0
Default Gateway.................: 192.168.2.1

Code: 
Tracing route to 192.169.4.101 over a maximum of 30 hops: 

  1   17 ms     10 ms     9 ms      192.168.2.1
  2   4 ms      *         10 ms     192.168.2.1
  3   *         6 ms      *         Request timed out.
  4   9 ms      *         10 ms     192.168.2.1
  5   *         8 ms      *         Request timed out.
  6   7 ms      *         8 ms      192.168.2.1
  7   *         7 ms      *         Request timed out.
  8   4 ms      *         9 ms      192.168.2.1
  9   *         6 ms      *         Request timed out.
  10   7 ms      *         8 ms      192.168.2.1
  11   *         8 ms      *         Request timed out.
  12   9 ms      *         6 ms      192.168.2.1
  13   *         8 ms      *         Request timed out.
  14   7 ms      *         7 ms      192.168.2.1
  15   *         9 ms      *         Request timed out.
...
  30   9 ms      *         8 ms      192.168.2.1
Trace complete.

Noe the other way around:
IP Address......................: 192.168.4.101
Subnet Mask.....................: 255.255.255.0
Default Gateway.................: 192.168.4.1
Code: 
Tracing route to 192.168.2.2 over a maximum of 30 hops: 

  1   16 ms     11 ms     18 ms     192.168.4.1
  2   *         *         *         Request timed out.
  3   19 ms     12 ms     14 ms     192.168.2.2

Trace complete.
 
Erugh, RIP :(
On Router 2, if you do
Show ip route 192.168.4.1
If you get subnet not in table, that's your problem
If it shows something like 192.168.4.0 /24 via 192.168.3.0 that's also a problem you need to point it at 192.168.3.2 (the linksys) is the linksys running RIP? Or is that static routes?
 
All the router settings were configured when I started so not changed anything. Think the best way for this is to show you images unless you have packet tracer installed!
http://imgur.com/a/uAZnS

So your saying add 192.168.4.0 to the RIP Routing table and delete the current static routes and make it 192.168.4.0/24 via 192.168.3.2?

Thanks,
 
RIP won't be doing anything if the other router router isn't running it. The route on R2 for 192.168.4.0/24 has to point at the next hop that knows where that network is, in this case the linksys 192.168.3.2 (not 3.0 which is the network number)
The default gateway for the linksys router is 3.1 which is R2, which knows where all the other networks are as they are directly connected (the router has an interface with an IP of the network)
 
Changed the route to 4.0 via 3.2, no difference.

I just can't get why the laptops can ping the desktops but not the other way, as Skid mentioned its a send and receive.

From a desktops I can ping the default gateway of the ISR (3.1) but thats it =/
 
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If you can ping one way then you've confirmed traffic is flowing both ways, so routing is probably not the issue else the return packet would be lost and ping would fail.

Are there any ACL's enabled?
 
192.168.1.x/192.168.2.x/192.168.3.x

They don't know how to get to 192.168.4.x

You need to advertise 192.168.4.x from the wireless router.
 
oli356 said:
From:
IP Address......................: 192.168.1.2
Subnet Mask.....................: 255.255.255.0
Default Gateway.................: 192.168.1.1
Code: 
PC>tracert 192.168.4.101

Tracing route to 192.168.4.101 over a maximum of 30 hops: 

  1   7 ms      5 ms      9 ms      192.168.1.1
  2   *         *         *         Request timed out.
  3   *         *         *         Request timed out.
  4   *         *         *         Request timed out.
  5   *         *         *         Request timed out.
  6   *         *         *         Request timed out.
  7   *         *         *         Request timed out.
  8   *         *         *         Request timed out.
Wasn't going anywhere.

From:
IP Address......................: 192.168.2.2
Subnet Mask.....................: 255.255.255.0
Default Gateway.................: 192.168.2.1

Code: 
Tracing route to 192.16[COLOR=Red]9[/COLOR].4.101 over a maximum of 30 hops: 

  1   17 ms     10 ms     9 ms      192.168.2.1
  2   4 ms      *         10 ms     192.168.2.1
  3   *         6 ms      *         Request timed out.
  4   9 ms      *         10 ms     192.168.2.1
  5   *         8 ms      *         Request timed out.
  6   7 ms      *         8 ms      192.168.2.1
  7   *         7 ms      *         Request timed out.
  8   4 ms      *         9 ms      192.168.2.1
  9   *         6 ms      *         Request timed out.
  10   7 ms      *         8 ms      192.168.2.1
  11   *         8 ms      *         Request timed out.
  12   9 ms      *         6 ms      192.168.2.1
  13   *         8 ms      *         Request timed out.
  14   7 ms      *         7 ms      192.168.2.1
  15   *         9 ms      *         Request timed out.
...
  30   9 ms      *         8 ms      192.168.2.1
Trace complete.
Noe the other way around:
IP Address......................: 192.168.4.101
Subnet Mask.....................: 255.255.255.0
Default Gateway.................: 192.168.4.1
Code: 
Tracing route to 192.168.2.2 over a maximum of 30 hops: 

  1   16 ms     11 ms     18 ms     192.168.4.1
  2   *         *         *         Request timed out.
  3   19 ms     12 ms     14 ms     192.168.2.2

Trace complete.
Click to expand...


2nd tracert can be ignored as you've traced to 192.169. not 192.168.
 
ots3go said:
If you can ping one way then you've confirmed traffic is flowing both ways, so routing is probably not the issue else the return packet would be lost and ping would fail.

Are there any ACL's enabled?
Click to expand...
Got a slight idea of what ACL is, looked around and no.
Skidilliplop said:
2nd tracert can be ignored as you've traced to 192.169. not 192.168.
Click to expand...
Won't work with the correct IP anyway ;)

This is been given to people who will be half way to getting a CCENT, thought it would be really easy. Doesn't help that I've never even seen things such as:
en
conf t
network 192.168.4.0
Click to expand...
Though as it's never been mentioned I can't see Cisco making us need to know.
 
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oli356 said:
Doesn't help that I've never even seen things such as:

Though as it's never been mentioned I can't see Cisco making us need to know.
Click to expand...

You will need to know. You can't do ANYTHING on ciscos without en + conf t.

and virtually every dynamic routing protocol needs network x.x.x.x in some form.
 
MilanoChris said:
You need to know RIP for CCENT.

I'll look at the exercise later, bit busy atm.
Click to expand...
Will probably come in later then, not sure how it's done normally but at college we use the cisco academy. So I'm doing working at a small-to-medium business or ISP. Done Discovery 1 (given this then), working through discovery 2, when I've completed that I can do the exam for the CCENT.
Only done a chapter 1,2,3 of Discovery 2 and they wern't really technical, on 4 now which is subnetting and there's 9 chapters.

Thanks :)

Skidilliplop said:
You will need to know. You can't do ANYTHING on ciscos without en + conf t.

and virtually every dynamic routing protocol needs network x.x.x.x in some form.
Click to expand...
Configuring network devices is my next chapter, talks about the IOS CLI etc
 
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The academy is a very slow way of learning, designed for college students learning for CCNA in semesters. You can teach it to yourself in a few weeks of hard study if you have a networking background or understand the fundamentals.

Get hold of Jeremy's CCNA (ICND 1 and ICND 2) nuggets, much faster and he explains everything so much better.

ICDN 1 is CCENT.
 
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