02-03-2011 03:53 AM - edited 03-06-2019 03:20 PM
Hi,
is it possible to set the switching method of a 2960G to Cut-throuh or Fragment free? Could somebody please post instructions on how to configure
and view the current switching mode which is used?
Thanks
R. Saendig
02-03-2011 04:57 AM
Hi,
is it possible to set the switching method of a 2960G to Cut-throuh or Fragment free?
As far as I know these are not supported on this platform. I think this is asics related.
Regards.
alain.
02-03-2011 05:17 AM
What about a Cisco 3560G? Is it possible to use Cut-Through or any other Method instead of Store n Foreward?
My mean Problem is while switching a Multicasting Stream from 1 Device to another the Switch receives the Multicast on port gi0/1
but does not send it out on another Port. I´ve used Wireshark and figured out that the Flag for dont fragment is set to 1 within the IP Header.
Any suggestions on how to resolve this issue?
R. Saendig
02-03-2011 05:39 AM
Hi,
My mean Problem is while switching a Multicasting Stream from 1 Device to another the Switch receives the Multicast on port gi0/1
but does not send it out on another Port. I´ve used Wireshark and figured out that the Flag for dont fragment is set to 1 within the IP Header.
A switch when forwarding frames is operating at Layer 2 and so doesn't care about the IP header.
The DF bit signifies the upstream router to not fragment the data if it should due to MTU being shorter on forward link than on receive link.
Is the port where the multicast stream is not forwarded in the same VLAN as others? if not then this is normal behaviour.
If not then maybe you've got CGMP or IGMP snooping on the switch.
Regards.
Alain.
02-03-2011 05:55 AM
The Ports are in the same vlan. IGMP Snooping is disabled.
Still the same Problem. I have connected another unmanagement switch from a other vendor and the traffic is going through.
So this is a Cisco releated Problem? I have tried 2960G & 3560G Switches.
Thanks for helping me out.
02-03-2011 06:39 AM
Hi ,
Can you post the running config of the switch, the version of IOS and the CAM table in this VLAN.
Regards.
Alain.
02-04-2011 12:41 AM
Switch#sh run
Building configuration...
Current configuration : 5143 bytes
!
version 12.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname Switch
!
boot-start-marker
boot-end-marker
!
!
username test privilege 15 secret 5 $1$Av2L$nmoZUhRhq3tVL7UhRpFl11
!
!
no aaa new-model
system mtu routing 1500
!
!
!
!
crypto pki trustpoint TP-self-signed-1445192448
enrollment selfsigned
subject-name cn=IOS-Self-Signed-Certificate-1445192448
revocation-check none
rsakeypair TP-self-signed-1445192448
!
!
crypto pki certificate chain TP-self-signed-1445192448
certificate self-signed 01
3082023F 308201A8 A0030201 02020101 300D0609 2A864886 F70D0101 04050030
31312F30 2D060355 04031326 494F532D 53656C66 2D536967 6E65642D 43657274
69666963 6174652D 31343435 31393234 3438301E 170D3933 30333031 30303032
31335A17 0D323030 31303130 30303030 305A3031 312F302D 06035504 03132649
4F532D53 656C662D 5369676E 65642D43 65727469 66696361 74652D31 34343531
39323434 3830819F 300D0609 2A864886 F70D0101 01050003 818D0030 81890281
8100BB6E 013A247E 5CA3E23F F00D1E80 7391175D A3DF7CBB 10AC0398 61D452BD
0613F032 9506A5DC 1049546D 289D537C 57B9FE17 3F39E957 37AEF904 1B68BB5F
766D059A 67D5937D A55FD1EC 739CFA5A B7E1C440 AAFB90DB D4FD678A 80B2C527
5351B657 10F3E3A6 5DA8648B 1889FF33 EC02061B 0BB1DF80 5760706F 9DC5CE40
F5970203 010001A3 67306530 0F060355 1D130101 FF040530 030101FF 30120603
551D1104 0B300982 07537769 7463682E 301F0603 551D2304 18301680 14B2B35C
F1A7A85B C534FB90 A619A369 6C84620C 7D301D06 03551D0E 04160414 B2B35CF1
A7A85BC5 34FB90A6 19A3696C 84620C7D 300D0609 2A864886 F70D0101 04050003
81810075 7D90BF00 DF95FC9E 7C444A23 E7B164E0 8FC00586 33B6D800 FF7FAB7D
3C485D2B B38B0854 72269E94 172680C3 5758D28E 7CFD1F14 985CB1A2 F7E281F2
AF5DBB17 AC5FFFB6 F20093A0 21440005 A44E2F2A B309FAE2 5D89CBC8 AE25361A
D4DEC0B2 BF3B1C3D 735CCE05 44C4DD89 37C9C783 066B59FF E0318012 97B24E04 D3813E
quit
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
!
!
interface GigabitEthernet0/1
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/2
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/3
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/4
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/5
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/6
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/7
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/8
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/9
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/10
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/11
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/12
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/13
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/14
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/15
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/16
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/17
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/18
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/19
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/20
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/21
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/22
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/23
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface GigabitEthernet0/24
spanning-tree portfast
spanning-tree bpdufilter enable
spanning-tree bpduguard enable
!
interface Vlan1
ip address 10.9.180.253 255.255.0.0
!
ip http server
ip http secure-server
ip sla enable reaction-alerts
!
line con 0
line vty 0 4
login
line vty 5 15
login
!
end
______________________________________________________________________________________________________________
Switch#sh ver
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 12.2(55)SE1, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2010 by Cisco Systems, Inc.
Compiled Thu 02-Dec-10 08:16 by prod_rel_team
Image text-base: 0x00003000, data-base: 0x01800000
ROM: Bootstrap program is C2960 boot loader
BOOTLDR: C2960 Boot Loader (C2960-HBOOT-M) Version 12.2(44)SE5, RELEASE SOFTWARE (fc1)
Switch uptime is 21 hours, 9 minutes
System returned to ROM by power-on
System image file is "flash:c2960-lanbasek9-mz.122-55.SE1.bin"
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
cisco WS-C2960G-24TC-L (PowerPC405) processor (revision E0) with 65536K bytes of memory.
Processor board ID FOC1217W76E
Last reset from power-on
1 Virtual Ethernet interface
24 Gigabit Ethernet interfaces
The password-recovery mechanism is enabled.
64K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address : 00:21:56:23:E3:00
Motherboard assembly number : 73-10015-06
Power supply part number : 341-0098-02
Motherboard serial number : FOC1217536B
Power supply serial number : AZS121508Z2
Model revision number : E0
Motherboard revision number : A0
Model number : WS-C2960G-24TC-L
System serial number : FOC1217W76E
Top Assembly Part Number : 800-26673-03
Top Assembly Revision Number : B0
Version ID : V03
CLEI Code Number : COM3G00BRB
Hardware Board Revision Number : 0x01
Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
* 1 24 WS-C2960G-24TC-L 12.2(55)SE1 C2960-LANBASEK9-M
Configuration register is 0xF
_________________________________________________________________________________________________________________
Switch#sh vlan
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Gi0/1, Gi0/2, Gi0/3, Gi0/4
Gi0/5, Gi0/6, Gi0/7, Gi0/8
Gi0/9, Gi0/10, Gi0/11, Gi0/12
Gi0/13, Gi0/14, Gi0/15, Gi0/16
Gi0/17, Gi0/18, Gi0/19, Gi0/20
Gi0/21, Gi0/22, Gi0/23, Gi0/24
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1 enet 100001 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
------------------------------------------------------------------------------
Primary Secondary Type Ports
------- --------- ----------------- ------------------------------------------
Switch#sh mac address-table vlan 1
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0180.c200.0000 STATIC CPU
All 0180.c200.0001 STATIC CPU
All 0180.c200.0002 STATIC CPU
All 0180.c200.0003 STATIC CPU
All 0180.c200.0004 STATIC CPU
All 0180.c200.0005 STATIC CPU
All 0180.c200.0006 STATIC CPU
All 0180.c200.0007 STATIC CPU
All 0180.c200.0008 STATIC CPU
All 0180.c200.0009 STATIC CPU
All 0180.c200.000a STATIC CPU
All 0180.c200.000b STATIC CPU
All 0180.c200.000c STATIC CPU
All 0180.c200.000d STATIC CPU
All 0180.c200.000e STATIC CPU
All 0180.c200.000f STATIC CPU
All 0180.c200.0010 STATIC CPU
All ffff.ffff.ffff STATIC CPU
1 000e.0cc6.0ee8 DYNAMIC Gi0/4
1 001c.230f.d091 DYNAMIC Gi0/2
1 00a0.f911.0e8a DYNAMIC Gi0/4
Total Mac Addresses for this criterion: 23
02-04-2011 02:04 AM
Hi,
So the multicast stream enters g0/1 and is flooded everywhere except on which port?
Can you explain the topology, how are the multicast recipients linked to the network and same for source.
What did you do with wireshark?
Post output of sh int status and sh spannning-tree as well as sh int g0/1 and sh int XX where XX is interface not flooded.
Regards.
Alain.
02-04-2011 02:29 AM
Switch#sh int stat
Vlan1
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 655 98491 5 320
Route cache 0 0 0 0
Total 655 98491 5 320
GigabitEthernet0/1
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 14834 1576243
Route cache 0 0 0 0
Total 0 0 14834 1576243
GigabitEthernet0/2
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 4454 476554
Route cache 0 0 0 0
Total 0 0 4454 476554
GigabitEthernet0/3
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/4
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 15152 1594304
Route cache 0 0 0 0
Total 0 0 15152 1594304
GigabitEthernet0/5
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/6
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/7
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/8
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/9
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/10
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/11
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/12
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/13
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/14
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/15
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/16
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/17
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/18
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/19
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/20
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/21
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/22
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/23
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
GigabitEthernet0/24
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 0 0
Route cache 0 0 0 0
Total 0 0 0 0
Switch#sh spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0021.5623.e300
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0021.5623.e300
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi0/1 Desg FWD 4 128.1 P2p Edge
Gi0/2 Desg FWD 4 128.2 P2p Edge
Gi0/4 Desg FWD 19 128.4 P2p Edge
attached to Gi0/2 and Gi0/3 are one workstation and one Laptop which i used to capture with wireshark.
The Stream enters Gi0/1 but does not get out of any Interface.
Thanks.
02-04-2011 02:46 AM
Hi,
It was sh interface status I wanted.
attached to Gi0/2 and Gi0/3 are one workstation and one Laptop which i used to capture with wireshark.
The Stream enters Gi0/1 but does not get out of any Interface.
Where is Gi0/3 in the output of sh span ? what was the multicast destination? Was the workstation listening to that traffic?---> nestat -rn
In wireshark did you leave promiscuous mode- were you seeing BPDUs? and the laptop with wireshark was listening to this traffic?----> netstat -rn
Regards.
alain.
02-04-2011 04:09 AM
Sorry my fault,
it´s not gi0/3 it was gi0/4....
Both were listen to...
Yes Wireshark is running in promiscuous Mode and Bpdu´s are been captured. Any Idea´s ?
Switch#sh int status
Port Name Status Vlan Duplex Speed Type
Gi0/1 connected 1 a-full a-1000 10/100/1000BaseTX
Gi0/2 connected 1 a-full a-1000 10/100/1000BaseTX
Gi0/3 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/4 connected 1 a-full a-100 10/100/1000BaseTX
Gi0/5 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/6 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/7 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/8 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/9 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/10 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/11 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/12 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/13 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/14 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/15 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/16 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/17 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/18 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/19 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/20 notconnect 1 auto auto 10/100/1000BaseTX
Gi0/21 notconnect 1 auto auto Not Present
Gi0/22 notconnect 1 auto auto Not Present
Gi0/23 notconnect 1 auto auto Not Present
Gi0/24 notconnect 1 auto auto Not Present
02-04-2011 04:23 AM
Hi,
I don't see anything in your config which could interfere with multicast flooding.
Can you ping this multicast address from a PC connected to Gi0/1 and post wireshark capture file on gi0/4
Regards.
Alain.
02-04-2011 04:48 AM
hi Alain,
thanks for your help so far. I will post it on Monday. I will use a local SPAN Configuration and post the output.
Thanks for helping me figuring out what the problem may cause.
Ronny
02-04-2011 05:14 AM
Hi Ronny,
I will use a local SPAN Configuration and post the output.
Use SPAN only for seeing Gi0/1 ingress traffic, to see the flooding on Gi0/4 just put a laptop with wireshark on it and capture in promiscuous.
Regards.
Alain.
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