12-24-2023 04:51 AM
Hi everyone,
I have C3560X switch which is the current core, trying to add a new switch C3850-24XS via the trunk port. The link status is up, I can see the lights on both ports physically. But no communication between the switches via trunk port, no CDP neighbours either. There is VTP on both switches, C3560X is server and C3850 is configured as client, I have double checked the passwords and they are good.
Any help is appreciated on getting this trunk up and running. I can provide more config info as required.
Below are some configurations.
C3560X side
ip routing
interface Vlan100
description Management VLAN
ip address 172.18.100.1 255.255.255.0
interface GigabitEthernet0/24
switchport trunk encapsulation dot1q
switchport trunk native vlan 100
switchport trunk allowed vlan 100
switchport mode trunk
sh int gi0/24 status
Port Name Status Vlan Duplex Speed Type
Gi0/24 new san test connected trunk a-full a-1000 10/100/1000BaseTX
VTP Version : running VTP2
Configuration Revision : 17
Maximum VLANs supported locally : 1005
Number of existing VLANs : 15
VTP Operating Mode : Server
VTP Domain Name : CDCCORPVTP1
VTP Pruning Mode : Disabled
VTP V2 Mode : Enabled
VTP Traps Generation : Disabled
MD5 digest : 0x89 0x03 0xC4 0x18 0xAD 0x3D 0xAD 0xB3
Configuration last modified by 0.0.0.0 at 3-1-93 00:20:35
Local updater ID is 172.18.2.1 on interface Vl2 (lowest numbered VLAN interface found)
C3850 side
ip routing
interface Vlan100
ip address 172.18.100.9 255.255.255.0
!
ip route 0.0.0.0 0.0.0.0 172.18.100.1
interface TenGigabitEthernet1/0/24
switchport trunk native vlan 100
switchport trunk allowed vlan 100
switchport mode trunk
sh int te1/0/24 status
Port Name Status Vlan Duplex Speed Type
Te1/0/24 connected trunk a-full a-1000 10/100/1000BaseTX SFP
sh vtp status
VTP Version capable : 1 to 3
VTP version running : 2
VTP Domain Name : CDCCORPVTP1
VTP Pruning Mode : Disabled
VTP Traps Generation : Disabled
Device ID : 0056.2bd9.1e80
Configuration last modified by 172.18.100.9 at 12-21-23 21:55:55
Feature VLAN:
--------------
VTP Operating Mode : Client
Maximum VLANs supported locally : 1005
Number of existing VLANs : 7
Configuration Revision : 0
MD5 digest : 0xB3 0x4C 0x27 0x65 0xCD 0x6D 0x7D 0x1C
0xAF 0x5B 0x02 0x3A 0x60 0x47 0xA0 0xAF
12-24-2023 11:10 AM
- Check logs on both devices when trunk is being made ,
M.
12-25-2023 11:24 AM
Would you be guide me on how to check that ? Thanks you
12-24-2023 02:32 PM - edited 12-24-2023 02:33 PM
Server says Number of vlan 15 and new switch show only 7 ?
If you shutdown one of the side interface admin down, Hope other side same connected interface go down ? (just to confirm plugged in right ports ?)
Can you try on the new switch VTP mode Transparent and add VLAN 100 Manually and test is that works ?
show vlan (check VLAN 100 exists)
show spanning vlan 100
show ip interface brief (check vlan 100 iSVI )interface up
12-25-2023 11:30 AM
I tried changing the VTP to transperent on client side (C3850) but that didn't work
More outputs on C3850
sh spanning-tree vlan 100
VLAN0100
Spanning tree enabled protocol rstp
Root ID Priority 32868
Address 0056.2bd9.1e80
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32868 (priority 32768 sys-id-ext 100)
Address 0056.2bd9.1e80
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Te1/0/24 Desg FWD 4 128.24 P2p
sh vlan br
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Te1/0/5, Te1/0/6, Te1/0/7, Te1/0/8, Te1/0/9, Te1/0/10, Te1/0/11, Te1/0/12, Te1/0/17
Te1/0/18, Te1/0/19, Te1/0/20, Te1/0/21, Te1/0/22, Te1/0/23
52 VLAN0052 active Te1/0/1, Te1/0/2, Te1/0/3, Te1/0/4, Te1/0/13, Te1/0/14, Te1/0/15, Te1/0/16
100 VLAN0100 active
1002 fddi-default act/unsup
1003 trcrf-default act/unsup
1004 fddinet-default act/unsup
1005 trbrf-default act/unsup
sh ip int vlan 100
Vlan100 is up, line protocol is up
Internet address is 172.18.100.9/24
Broadcast address is 255.255.255.255
Address determined by non-volatile memory
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing Common access list is not set
Outgoing access list is not set
Inbound Common access list is not set
Inbound access list is not set
Proxy ARP is enabled
Local Proxy ARP is disabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is enabled
IP Flow switching is disabled
IP CEF switching is enabled
IP CEF switching turbo vector
IP Null turbo vector
Associated unicast routing topologies:
Topology "base", operation state is UP
IP multicast fast switching is enabled
IP multicast distributed fast switching is disabled
IP route-cache flags are Fast, CEF
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
IPv4 WCCP Redirect outbound is disabled
IPv4 WCCP Redirect inbound is disabled
IPv4 WCCP Redirect exclude is disabled
12-24-2023 03:35 PM
@RookieNet55 wrote:
no CDP neighbours either
What is the uptime of the 3850 switch and what firmware is the 3850 running on?
12-25-2023 11:31 AM
Uptime is about 3 days. C3850 is running on 16.12.10a
12-25-2023 11:50 AM
how come you have VLAN 100 root here : it suppose to be root on at 3650 since that is already holding VLAN 100 ?
This bridge is the root
what you see on Cat 3650 ?
sh spanning-tree vlan 100
show interface Te1/0/24 switchport (from Cat 3850)
show interface Te1/0/24
show interface GigabitEthernet0/24 switchport (from Cat 3650)
show interface GigabitEthernet0/24
12-25-2023 12:00 PM
So what I did was before putting this C3850 switch on VTP, I created vlan 100 manually on this switch. So this switch can communicate over the trunk with vlan 100 and get all the VTP information. Would this be causing any conflict.
Fw more details, I beleive there is no layer 2 communication at all at this point, though physical link is good per "sh interface command". No CDP neighbours and also no arp entries.
Below are requested command outputs
On C3850
sh int te1/0/24 switchport
Name: Te1/0/24
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 100 (VLAN0100)
Administrative Native VLAN tagging: disabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: 100
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Vepa Enabled: false
Appliance trust: none
On C3650
sh int gi0/24 switchport
Name: Gi0/24
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 100 (mgmt)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: 100
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none
sh int gi0/24
GigabitEthernet0/24 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 0018.7392.c618 (bia 0018.7392.c618)
Description: new san test
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:00:01, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
256773 packets output, 22913303 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
12-25-2023 01:11 PM
what you see on Cat 3650 ? (if you see on this also root - then looks like you have Layer 2 issue.
sh spanning-tree vlan 100
To fix this : make sure VLAN 100 Root in Cat 3650 (and VLAN 100 created)
If at 3850 not in production (remove the link between both the switches ?) - Remove all the VLANS and make VTP transparent - Write the config reload..
Once the switch come back, create vlan 100 - connect the port and test it.
12-25-2023 01:33 PM
Here is what I did based on your directions
on C3850 :
12-25-2023 02:34 PM
what you see on Cat 3650 ?
sh spanning-tree vlan 100
For testing can we make p2p interface and test :
Try layer 3 interface to confirm all ok :
interface Te1/0/24
no switchport
ip address 10.10.10.1 255.255.255.0 (make sure there no other device configured same IP)
no shutdown
Other switch
interface GigabitEthernet0/24
no switchport
ip address 10.10.10.2 255.255.255.0
no shut
connect cables and test pinging each other 10.10.10.1 and 10.10.10.2
12-25-2023 02:56 PM
out put of spanning tree on vlan 100 on C3650
VLAN0100
Spanning tree enabled protocol ieee
Root ID Priority 32868
Address 0018.7392.c600
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32868 (priority 32768 sys-id-ext 100)
Address 0018.7392.c600
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi0/2 Desg FWD 4 128.2 P2p
Gi0/3 Desg FWD 4 128.3 P2p
Gi0/23 Desg FWD 4 128.23 P2p
Gi0/24 Desg FWD 4 128.24 P2p
The other ports are the other switches in production which are working fine.
When I change the port to ip address would this need a anything on the ip route, or it should work once the ports are changed to layer 3
12-26-2023 08:37 AM - edited 12-26-2023 08:39 AM
The other ports are the other switches in production which are working fine. - Ok noted
When I change the port to ip address would this need a anything on the ip route, or it should work once the ports are changed to layer 3
this is to prove the ports are working.
Full-duplex, 1000Mb/s, link type is auto, media type is 10/100/1000BaseTX SFP
Are sure you connected each other connected right ports ? - I have asked before, if you remove the cable other end did the port gone down ?
what is the full model of the both the switches ?
did you tried different ports ? - changing to different ports ?
From 3850 post complete below output :
#show interface status
If the switch is ws-c3850-24
then configure using - interface GigabitEthernet1/0/24
12-26-2023 09:30 AM - edited 12-26-2023 09:34 AM
Are sure you connected each other connected right ports ? - I have asked before, if you remove the cable other end did the port gone down ?
yes it is connected to right ports, I shutdown the port on one side and the other side port will go down. I am not at site today, but will be tomorrow. But even then for your question, yes the ports are physically connected to the right ports.
what is the full model of the both the switches ?
Core Switch in production:
Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
* 1 52 WS-C3560G-48TS 12.2(46)SE C3560-ADVIPSERVICESK9-M
New switch trying to add:
Switch Ports Model SW Version SW Image Mode
------ ----- ----- ---------- ---------- ----
* 1 34 WS-C3850-24XS 16.12.10a CAT3K_CAA-UNIVERSALK9 INSTALL
sh int status
Port Name Status Vlan Duplex Speed Type
Te1/0/1 notconnect 52 auto auto unknown
Te1/0/2 notconnect 52 auto auto unknown
Te1/0/3 notconnect 52 auto auto unknown
Te1/0/4 notconnect 52 auto auto unknown
Te1/0/5 notconnect 1 auto auto unknown
Te1/0/6 notconnect 1 auto auto unknown
Te1/0/7 notconnect 1 auto auto unknown
Te1/0/8 notconnect 1 auto auto unknown
Te1/0/9 notconnect 1 auto auto unknown
Te1/0/10 notconnect 1 auto auto unknown
Te1/0/11 notconnect 1 auto auto unknown
Te1/0/12 notconnect 1 auto auto unknown
Te1/0/13 notconnect 52 auto auto unknown
Te1/0/14 notconnect 52 auto auto unknown
Te1/0/15 notconnect 52 auto auto unknown
Te1/0/16 notconnect 52 auto auto unknown
Te1/0/17 notconnect 1 auto auto unknown
Te1/0/18 notconnect 1 auto auto unknown
Te1/0/19 notconnect 1 auto auto unknown
Te1/0/20 notconnect 1 auto auto unknown
Te1/0/21 notconnect 1 auto auto unknown
Te1/0/22 notconnect 1 auto auto unknown
Te1/0/23 notconnect 1 auto auto unknown
Te1/0/24 connected trunk a-full a-1000 10/100/1000BaseTX SFP
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