it's baby time... grab your pablum and bibs... don't forget to drool...
here is an interesting thought... you want to know the various devices connected via vlans from one switch, dls1 in this case... you have a number of commands that will help you assemble this information, you don't however have a command that will quickly map it out for you...
try and you'll see that you actually have to piece this information together... we have been in vlan denial all these years... show vlan doesn't give a shit about the trunks...
DLS1#sh vlan brie
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active
10 OFFICE active
20 VOICE active
30 GUEST active
50 SERVERS active Fa0/6
100 MGMT active
900 NATIVE active
999 UNUSED active Fa0/7, Fa0/8, Fa0/9, Fa0/10
Fa0/11, Fa0/12, Fa0/13, Fa0/14
Fa0/15, Fa0/16, Fa0/17, Fa0/18
Fa0/19, Fa0/20, Fa0/21, Fa0/22
Fa0/23, Fa0/24, Gi0/1, Gi0/2
that's a start anyway...
DLS1#sh vlan id 50
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
50 SERVERS active Fa0/6, Po10
funny i never really thought about this... we have a lock on f0/6 and portchannel 10... of course i know what devices they are connected to, but is the output giving it up...
DLS1#sh etherch summ | b Group
Group Port-channel Protocol Ports
------+-------------+-----------+-----------------------------------------------
1 Po1(SU) - Fa0/1(P) Fa0/2(P)
10 Po10(SU) - Fa0/3(P) Fa0/4(P)
po10 has f0/3 - 4, but what are they connected to, and would you ever rely on a description?
DLS1#sh int po10 trunk
Port Mode Encapsulation Status Native vlan
Po10 on 802.1q trunking 900
Port Vlans allowed on trunk
Po10 10,20,30,50,100
Port Vlans allowed and active in management domain
Po10 10,20,30,50,100
Port Vlans in spanning tree forwarding state and not pruned
Po10 10,20,30,50,100
that's a great command... f0/3 - 4 are definitely supporting native vlan 900 as well as vlans 10,20,30,50 and 100...
DLS1#sh cdp neigh | b Device
Device ID Local Intrfce Holdtme Capability Platform Port ID
R1.tshoot.net Fas 0/5 125 R S I 2611XM Fas 0/0
ALS1.tshoot.net Fas 0/1 166 S I WS-C3550- Fas 0/1
ALS1.tshoot.net Fas 0/2 166 S I WS-C3550- Fas 0/2
DLS2.tshoot.net Fas 0/4 164 R S I WS-C3560- Fas 0/4
DLS2.tshoot.net Fas 0/3 164 R S I WS-C3560- Fas 0/3
good ole faithful cdp neighbor, but what if it was turned off?
DLS1#sh int f0/4
FastEthernet0/4 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 0016.c706.9686 (bia 0016.c706.9686)
Description: Channel to DLS2
it's nice that the description is correct in this case...
DLS1#sh int f0/4 sw
Name: Fa0/4
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk (member of bundle Po10)
ultimately this exercise brings up the importance of documentation, diagrams...
don't forget this command (although it is reliant on description and isn't a big help with the vlan to trunk connection)
DLS1#sh int status
Port Name Status Vlan Duplex Speed Type
Fa0/1 Channel to ALS1 connected trunk a-full a-100 10/100BaseTX
Fa0/2 Channel to ALS1 connected trunk a-full a-100 10/100BaseTX
Fa0/3 Channel to DLS2 connected trunk a-full a-100 10/100BaseTX
Fa0/4 Channel to DLS2 connected trunk a-full a-100 10/100BaseTX
Fa0/5 FE to R1 connected routed full 100 10/100BaseTX
Fa0/6 FE to SRV1 notconnect 50 auto auto 10/100BaseTX
Fa0/7 Unused disabled 999 auto auto 10/100BaseTX
Fa0/8 Unused disabled 999 auto auto 10/100BaseTX
Fa0/9 Unused disabled 999 auto auto 10/100BaseTX
Fa0/10 Unused disabled 999 auto auto 10/100BaseTX
Fa0/11 Unused disabled 999 auto auto 10/100BaseTX
Fa0/12 Unused disabled 999 auto auto 10/100BaseTX
Fa0/13 Unused disabled 999 auto auto 10/100BaseTX
Fa0/14 Unused disabled 999 auto auto 10/100BaseTX
Fa0/15 Unused disabled 999 auto auto 10/100BaseTX
Fa0/16 Unused disabled 999 auto auto 10/100BaseTX
Fa0/17 Unused disabled 999 auto auto 10/100BaseTX
Fa0/18 Unused disabled 999 auto auto 10/100BaseTX
Fa0/19 Unused disabled 999 auto auto 10/100BaseTX
Fa0/20 Unused disabled 999 auto auto 10/100BaseTX
Fa0/21 Unused disabled 999 auto auto 10/100BaseTX
Port Name Status Vlan Duplex Speed Type
Fa0/22 Unused disabled 999 auto auto 10/100BaseTX
Fa0/23 Unused disabled 999 auto auto 10/100BaseTX
Fa0/24 Unused disabled 999 auto auto 10/100BaseTX
Gi0/1 Unused disabled 999 auto auto Not Present
Gi0/2 Unused disabled 999 auto auto Not Present
Po1 Channel to ALS1 connected trunk a-full a-100
Po10 Channel to DLS2 connected trunk a-full a-100
where is the command show vlans connected?
i have read that for the ccie lab you will be able to count on the documentation as well as the descriptions... but what about an evil proctor?
network cisco ccna gns3 certification arteq
a network runs through it
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