Journal

I'm not sure that I'm not going to regret doing this, but following in the footsteps of making a thread for my progress towards the IE.

Last night I grabbed a pdf for the routing & switching cert guide (I don't feel guilty about doing this, as the actual book has been purchased and is in transit. I may get it tomorrow or Monday at the latest - I just wanted to get started).

Read for about 3 hours last night and made it through Chapter 1 and most of Chapter 2. Everything seemed pretty easy / review until I came to a screeching halt at the end of Chapter 2 with the sudden introduction of PPPoE. Tried making sense of it for a while but gave up on it. I'll be looking at it more tonight, but may just make a note and move on. I'm hoping it'll make more sense on the re-read. That worked pretty well for a few areas in the Route studies.

To me learning is kindof like putting together a puzzle. It's much easier to do if you're adding to something you already know/have done. This surprise PPPoE felt like I was suddenly working on a totally new area of a puzzle where I didn't even have 2 pieces together yet.

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Comments

bermovick

Work has been busy and chaotic and extremely stressful the past month. The contract changed hands and the new company is ... less competent than the previous one.

Our server team no longer has certified people so they aren't allowed to touch servers. Instead our COR has the network team (all 2 of us) working the servers, despite neither of us being certified either. Plus the new company being out of compliance with the contract pretty much since day 1 leaves our future employment a bit shaky....

So I haven't spent much of the past month studying. However I just found out my friend got his numbers yesterday (his 3rd try), so I need to try to get better at focusing and get my ass my numbers too. Tonight I'm actually studying instead of playing my MMO.

INE full-size lab 1. Doing well, although complex redistribution is STILL my weakest point, I think. When you've got 3 routing protocols plus connected redistribution, with 4 points of redistribution (not counting the connected->protocol), it's just difficult getting it in my head. Then I google examples and they're all "here's 2 protocols with 2 redistribution points" as if that's even the same ballpark. I managed to get the topology stable, but I had to use the "throw everything at it until something works" method, which isn't the best one.

bermovick

Ran into a weird thing today going into multicast since it's been a while since I touched it last. I was being lazy and using the (*,224.0.1.40) route that gets automatically installed as verification I had a good config, but I kept getting confused because that mroute didn't look correct.

I still don't know why, but that mroute seems to (randomly?) leave out interfaces from its Outgoing interface list:

R5#sh ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
       L - Local, P - Pruned, R - RP-bit set, F - Register flag,
       T - SPT-bit set, J - Join SPT, M - MSDP created entry,
       X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
       U - URD, I - Received Source Specific Host Report,
       Z - Multicast Tunnel, z - MDT-data group sender,
       Y - Joined MDT-data group, y - Sending to MDT-data group
Outgoing interface flags: H - Hardware switched, A - Assert winner
 Timers: Uptime/Expires
 Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 239.1.1.1), 00:02:25/stopped, RP 0.0.0.0, flags: D
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    FastEthernet0/1, Forward/Dense, 00:02:25/00:00:00
    FastEthernet0/0, Forward/Dense, 00:02:25/00:00:00
    FastEthernet1/0, Forward/Dense, 00:02:25/00:00:00

[snip]

(*, 224.0.1.40), 01:26:50/00:02:48, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    FastEthernet0/0, Forward/Dense, 01:21:00/00:00:00
    FastEthernet1/0, Forward/Dense, 01:26:50/00:00:00

I actually had to troubleshoot for a while why F0/1 wasn't in the 224.0.1.40 mroute, assuming I had some misconfiguration.

bermovick

See, this is confusing me: I expect a certain output but I don't get it. Take a look at this:

This is a simple diamond of 4 routers (think 12, 3, 6, 9 on a clock). Router "R6" is doing autorp advertisements (it's both a CRP and mapping agent). "R12" should be receiving info from the other 2 (R3 & R9), and I expect to see both interfaces in the (*,G) mroute's Outgoing Interface list. I should then see one of them (the one that passes the RPF check) as the Incoming Interface of the (S,G) mroute, correct?

That's what I see on the routers in the middle "R3" and "R9"

(*, 224.0.1.40), 20:18:33/stopped, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    FastEthernet0/0, Forward/Dense, 20:18:33/00:00:00
    FastEthernet0/1, Forward/Dense, 20:18:33/00:00:00

(6.6.6.6, 224.0.1.40), 20:18:32/00:02:59, flags: LT
  Incoming interface: FastEthernet0/1, RPF nbr 192.168.69.6
  Outgoing interface list:
    FastEthernet0/0, Forward/Dense, 20:18:32/00:00:00, A

But not on "R12"

(*, 224.0.1.40), 4d20h/stopped, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    FastEthernet0/0, Forward/Dense, 4d20h/00:00:00

(6.6.6.6, 224.0.1.40), 20:12:03/00:02:59, flags: PLT
  Incoming interface: FastEthernet0/1, RPF nbr 192.168.123.3
  Outgoing interface list:
    FastEthernet0/0, Prune/Dense, 00:01:27/00:01:32

Am I missing a step? I can't find anything that would explain why the (*,G) is missing F0/1.

AwesomeGarrett

I'd hate to jump to conclusions. Do you have config snippets? PIM, Auto-RP, IGP, and interfaces? Are you following an example from Cisco Docs?

bermovick

No; I was having trouble with the multicast section of an INE workbook so I wrote up a small custom lab.

I changed the router numbers in my previous post to make it easier to visualize. The section I'm looking at are actually routers 1-4.

Here's the ACTUAL unedited mroute on R1:

(*, 224.0.1.40), 4d21h/stopped, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    FastEthernet0/0, Forward/Dense, 4d21h/00:00:00

(4.4.4.4, 224.0.1.40), 21:07:15/00:02:58, flags: L
  Incoming interface: FastEthernet0/1, RPF nbr 192.168.13.3
  Outgoing interface list:
    FastEthernet0/0, Forward/Dense, 00:00:00/00:00:00

(as a test, I created a /0 mroute pointing to R2 instead to see how the output would change with the RPF change, and it equally made no sense):

(*, 224.0.1.40), 4d21h/stopped, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    FastEthernet0/0, Forward/Dense, 4d21h/00:00:00

(4.4.4.4, 224.0.1.40), 21:06:40/00:02:58, flags: PLT
  Incoming interface: FastEthernet0/0, RPF nbr 192.168.12.2, Mroute
  Outgoing interface list: Null

Nothing fancy with the config either:

R4:

R4#sh run | s pim|0/0|0/1
 ip pim dense-mode
interface FastEthernet0/0
 ip address 192.168.34.4 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
interface FastEthernet0/1
 ip address 192.168.24.4 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
 ip pim dense-mode
ip pim send-rp-announce Loopback0 scope 10 interval 1
ip pim send-rp-discovery Loopback0 scope 10 interval 1

R2:

R2# sh run | s pim|0/0|0/1
 ip pim dense-mode
interface FastEthernet0/0
 ip address 192.168.12.2 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
interface FastEthernet0/1
 ip address 192.168.24.2 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
 ip pim dense-mode
ip pim autorp listener

R3:

R3#sh run | s pim|0/0|0/1
 ip pim dense-mode
interface FastEthernet0/0
 ip address 192.168.34.3 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
interface FastEthernet0/1
 ip address 192.168.13.3 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
 ip pim dense-mode
ip pim autorp listener

R1:

R1#sh run | s pim|0/0|0/1
 ip pim dense-mode
interface FastEthernet0/0
 ip address 192.168.12.1 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
interface FastEthernet0/1
 ip address 192.168.13.1 255.255.255.0
 ip pim dense-mode
 ip ospf network point-to-point
 ip ospf 1 area 0
 duplex auto
 speed auto
 ip pim dense-mode

screenshot.jpg

Dieg0M

What IOS are you using? I am pretty sure that all hosts and PIM neighbor interfaces should be in the shared tree of a PIM-DM group.

bermovick

That's what I thought! This was in gns3. I'll duplicate the lab in IOU and see if I get correct results then.

bermovick

I spend FAR too much of my time messing with unrelated crap.

GNS3 multicast that doesn't make sense (see above).
IOU crashes that I've spent the last 3 days trying to figure out.

I've never had any issue going through labs, but now as soon as I send traffic over ONE of the 4 switches, it crashes
../src-unix/unix_io.c:561: unix_io_transmit: Assertion `chan_p != ((void *)0)' failed.

Why only the one? Why has it never crashed before when doing the labs? You tell me. I can't even finish the lab at this point.

Sometimes I think the universe is trying to send me a message cause I google this and NOBODY else has ever had any of these problems. Sheesh!

linuxabuser

Buy VIRL, save yourself some headaches.

fredrikjj

linuxabuser wrote: »

Buy VIRL, save yourself some headaches.

Not really. Multicast for example is kind of buggy on IOSv, and who knows what else. CSR is where you need to go since it's supposed to be used for real environments, not just a lab, and you don't need VIRL to run CSR1000v.

bermovick

The only issue I've really had with CSR is it's memory requirements, and not having enough "current" physical switches to do the INE labs.

The memory requirements can be worked around with an ESX server we bought for labbing (my wife is using it for her MCSA as well), but no switches are kindof a sticking point.

I might check and see how much I can do with my 1950's, 3550 and 3560 though. But that's more time spent frelling with stuff outside of what I should actually be studying for