CCIE Pursuit Blog

April 28, 2008

Question Of The Day: 28 April, 2008

Topic: Frame Relay Traffic Shaping

Here is the current configuration for r1’s Frame Relay connection:

interface Serial1/0
 no ip address
 encapsulation frame-relay
!
interface Serial1/0.12 point-to-point
 ip address 10.1.12.1 255.255.255.0
 frame-relay interface-dlci 102

Configure r1 to match this output:

r1#show traffic-shape

Interface   Se1/0.12
       Access Target    Byte   Sustain   Excess    Interval  Increment Adapt
VC     List   Rate      Limit  bits/int  bits/int  (ms)      (bytes)   Active
102           512000    9600   51200     25600     100       6400      BECN

Click Here For The Answer


Yesterday’s Question

Question Of The Day: 25 April, 2008 

Topic: EIGRP

r1 and r2 are directly connected via their respective fa0/0 interfaces:

r1:
interface FastEthernet0/0
  ip address 10.1.12.1
  ip hold-time eigrp 100 30
  ip hello-interval eigrp 100 5
!
router eigrp 100
  no auto-summary
  network 10.1.12.1 0.0.0.0

r2:
interface FastEthernet0/0
  ip address 10.1.12.2
  ip hold-time eigrp 100 60
  ip hello-interval eigrp 100 10
!
router eigrp 100
  no auto-summary
  network 10.1.12.2 0.0.0.0

Will r1 and r2 for an EIGRP neighbor relationship over the Ethernet link between them?

Answer: Yes

I have to admit that this one seems counter-intuitive to me.  If you create a mismatch of the EIGRP hello and hold-times (provided that you do not configure a hold-time that is less than the hello interval) on each side of a link, the EIGRP neighbor relationship will not be affected.

r1#show ip eigrp interfaces detail | i Inter|Fa0/0|Hello
Interface        Peers  Un/Reliable  SRTT   Un/Reliable   Flow Timer   Routes
Fa0/0              1        0/0       249       0/10         856           0
  Hello interval is 5 sec

r2#show ip eigrp interfaces detail | i Inter|Fa0/0|Hello
Interface        Peers  Un/Reliable  SRTT   Un/Reliable   Flow Timer   Routes
Fa0/0              1        0/0       295       0/10        1216           0
  Hello interval is 10 sec

I did a ‘debug ip packet detail’ on r1.  You can see that the EIGRP hellos are going out every (approximately) every 5 seconds:

r1#sh log | i s=10.1.12.1
*Mar  1 00:32:29.383: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:32:33.999: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:32:38.895: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:32:43.323: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:32:48.075: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:32:52.743: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:32:57.287: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:33:01.815: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:33:06.619: IP: s=10.1.12.1 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88

Same thing on r2.  The EIGRP hellos are going out (approximately) every 10 seconds:

r2#sh log | i s=10.1.12.2
*Mar  1 00:37:30.755: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:37:39.931: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:37:49.467: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:37:58.447: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:38:07.831: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:38:16.371: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:38:25.899: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:38:34.755: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88
*Mar  1 00:38:43.463: IP: s=10.1.12.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast, proto=88

The EIGRP neighbors are up and stable, and routes are be advertised:

r1#show ip eigrp neighbors detail fa0/0
IP-EIGRP neighbors for process 100
H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                            (sec)         (ms)       Cnt Num
0   10.1.12.2               Fa0/0             59 00:41:49  249  1494  0  6
   Version 12.3/1.2, Retrans: 1, Retries: 0, Prefixes: 2

r1#sh ip route eigrp
     100.0.0.0/24 is subnetted, 1 subnets
D       100.1.4.0 [90/158720] via 10.1.12.2, 00:43:13, FastEthernet0/0
     10.0.0.0/24 is subnetted, 4 subnets
D       10.1.24.0 [90/30720] via 10.1.12.2, 00:43:14, FastEthernet0/0

r2#show ip eigrp neighbors detail fa0/0
IP-EIGRP neighbors for process 100
H   Address                 Interface       Hold Uptime   SRTT   RTO  Q  Seq
                                            (sec)         (ms)       Cnt Num
0   10.1.12.1               Fa0/0             26 00:45:17  249  1494  0  5
   Version 12.3/1.2, Retrans: 1, Retries: 0, Prefixes: 1

r2#show ip route eigrp
     1.0.0.0/32 is subnetted, 1 subnets
D       1.1.1.1 [90/156160] via 10.1.12.1, 00:00:16, FastEthernet0/0

So the answer is yes.  🙂

 

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2 Comments »

  1. […] by Question Of The Day: 28 April, 2008 « CCIE Pursuit — April 28, 2008 @ 8:24 […]

    Pingback by Question Of The Day: 25 April, 2008 « CCIE Pursuit — April 28, 2008 @ 8:25 am | Reply

  2. […] Question Of The Day: 28 April, 2008  […]

    Pingback by Question Of The Day: 29 April, 2008 « CCIE Pursuit — April 29, 2008 @ 8:06 am | Reply


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