Unable to set an IP address on subinterfaces

I'm trying to setup a router-on-a-stick config in my practice lab but for some reason I'm unable to configure the subinterface as part of an 802.1q. I know that I have to type encapsulation dot1q and the associated vlan but the command is detected as invalid. When I use the help command, encapsulation is not even included in the list.

R2#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
R2(config)#int f0/0.20
R2(config-subif)#ip address 192.168.20.1 255.255.255.0


% Configuring IP routing on a LAN subinterface is only allowed if that
subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q,
or ISL vLAN.


R2(config-subif)#?
Interface configuration commands:
  arp             Set arp type (arpa, probe, snap) or timeout
  backup          Modify backup parameters
  bandwidth       Set bandwidth informational parameter
  bgp-policy      Apply policy propagated by bgp community string
  bridge-group    Transparent bridging interface parameters
  cdp             CDP interface subcommands
  default         Set a command to its defaults
  delay           Specify interface throughput delay
  description     Interface specific description
  exit            Exit from interface configuration mode
  glbp            Gateway Load Balancing Protocol interface commands
  ip              Interface Internet Protocol config commands
  keepalive       Enable keepalive
  llc2            LLC2 Interface Subcommands
  mtu             Set the interface Maximum Transmission Unit (MTU)
  netbios         Use a defined NETBIOS access list or enable name-caching
  no              Negate a command or set its defaults
  ntp             Configure NTP
  rate-limit      Rate Limit
  service-policy  Configure QoS Service Policy
  shutdown        Shutdown the selected interface
  snapshot        Configure snapshot support on the interface
  snmp            Modify SNMP interface parameters
  standby         HSRP interface configuration commands
  timeout         Define timeout values for this interface
  traffic-shape   Enable Traffic Shaping on an Interface or Sub-Interface
  vrrp            VRRP Interface configuration commands

Any thoughts?

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Comments

gosh1976

Do a show version command and post up the first part of it.

Michael2

I've got an idea. Look at your tutorial again. If you don't have your tutorial, cancel the test and take something else. Cisco is very difficult and it's best to have some field experience before taking it to avoid having to retake it several times.

pham0329

Michael2 wrote: »

I've got an idea. Look at your tutorial again. If you don't have your tutorial, cancel the test and take something else. Cisco is very difficult and it's best to have some field experience before taking it to avoid having to retake it several times.

You're telling someone to stop pursuing Cisco certification because his router won't allow him to assign an ip address to a sub-interface? Cisco's exam are not "very difficult", they just require you to have a good understanding of the concepts and the IOS.

MrRyte

R2#conf t
Enter configuration commands, one per line. End with CNTL/Z.
R2(config)#int f0/0.20
R2(config-subif)#encap dot1q 20
R2(config-subif)#ip address 192.168.20.1 255.255.255.0

That's what's missing.

gosh1976

MrRyte wrote: »

That's what's missing.

he is saying that he gets an invalid command error when he tries that and when he types ? encapsulation is not included in the list. It's probably due to the IOS version.

abst2act

Michael2 wrote: »

I've got an idea. Look at your tutorial again. If you don't have your tutorial, cancel the test and take something else. Cisco is very difficult and it's best to have some field experience before taking it to avoid having to retake it several times.

I have a better idea, punch yourself in the face. Cisco is actually not that difficult as I passed the CCENT exam first try. Do all of us a favor and keep your responses to yourself.

abst2act

pham0329 wrote: »

You're telling someone to stop pursuing Cisco certification because his router won't allow him to assign an ip address to a sub-interface? Cisco's exam are not "very difficult", they just require you to have a good understanding of the concepts and the IOS.

Amen brother

abst2act

gosh1976 wrote: »

he is saying that he gets an invalid command error when he tries that and when he types ? encapsulation is not included in the list. It's probably due to the IOS version.

I have a feeling you are right. I actually thought about that but forgot to check as I was in a rush to leave. I will check and post the version when I get a chance.

MrRyte

gosh1976 wrote: »

he is saying that he gets an invalid command error when he tries that and when he types ? encapsulation is not included in the list. It's probably due to the IOS version.

My apologies for overlooking that part.

abst2act

Thanks gosh1976! You were right. Luckily I had another router with ver 12.4 and I was able to configure the subinterface just fine.

billyr

Now go back and try the older IOS version. As suggested by MrRyte, this time apply the encapsulation before you try to add the I.P address, that is the problem. Nothing to do with the IOS.

pham0329

billyr wrote: »

Now go back and try the older IOS version. As suggested by MrRyte, this time apply the encapsulation before you try to add the I.P address, that is the problem. Nothing to do with the IOS.

He said he tried to do the encapsulation command, and it didn't work. It didn't even show up under the help menu. Or are you saying that once you do the ip address command, the IOS removes the encapsulation command?

billyr

pham0329 wrote: »

He said he tried to do the encapsulation command, and it didn't work. It didn't even show up under the help menu. Or are you saying that once you do the ip address command, the IOS removes the encapsulation command?

Go back and read his original post again. You are correct, he did say he tried the encapsulation command and that he found it wasn't there. What he didn't say though was that he actually tried the correct method of selecting the encapsulaiton method before applying the I.P address.

I'm trying to setup a router-on-a-stick config in my practice lab but for some reason I'm unable to configure the subinterface as part of an 802.1q. I know that I have to type encapsulation dot1q and the associated vlan but the command is detected as invalid. When I use the help command, encapsulation is not even included in the list.

The reason the command was invalid and not showing in IOS help is that he was trying to apply the command in the wrong order.

R2(config)#int f0/0.20
R2(config-subif)#ip address 192.168.20.1 255.255.255.0

% Configuring IP routing on a LAN subinterface is only allowed if that
subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q,
or ISL vLAN.

Monkerz

abst2act wrote: »

I have a better idea, punch yourself in the face. Cisco is actually not that difficult as I passed the CCENT exam first try. Do all of us a favor and keep your responses to yourself.

This isn't youtube, ebaumsworld, or any other site where trolling is tolerated. If you have nothing nice to say, say nothing at all.

pham0329

billyr wrote: »

The reason the command was invalid and not showing in IOS help is that he was trying to apply the command in the wrong order.

I'm going to have to test this out. I've done this in the past (enter ip before encap command) and although it would bark at me, it always allowed me to enter in the encaps command afterward.

EDIT: Ok, tested it in GNS3. Even if I enter the ip address command first, it'd still allow me to do the encap after.

R1#
R1#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
R1(config)#int fa 0/0.100
R1(config-subif)#ip add 192.168.1.1 255.255.255.0

% Configuring IP routing on a LAN subinterface is only allowed if that
subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q,
or ISL vLAN.

R1(config-subif)#?
Interface configuration commands:
  ....
  delay           Specify interface throughput delay
  description     Interface specific description
  [COLOR=#ff0000]encapsulation   Set encapsulation type for an interface[/COLOR]
  exit            Exit from interface configuration mode
  flow-sampler    Attach flow sampler to the interface
  ....

R1(config-subif)#[COLOR=#ff0000]encap dot1q 20[/COLOR]
R1(config-subif)#

billyr

bangs head on wall!!!

Of course you can enter the Encaps command afterwards, that's what the error message is telling you to do, it is telling you, you were missing the encaps command, that is why you had an error message in the first place. It now requires you to enter the encapsulation. However when you do so, you will find that your I.P address wouldn't have taken effect.

However if you configure it in the correct order you won't have any error message.

Check below:

Example 1 using the incorrect method:

est_Router(config)#int f0/0
Test_Router(config-if)#no shut
Test_Router(config-if)#int f0/0.1
Test_Router(config-subif)#ip add 192.168.1.254 255.255.255.0

% Configuring IP routing on a LAN subinterface is only allowed if that
subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q,
or ISL vLAN.
Test_Router(config-subif)#encaps dot1q 1
Test_Router(config-subif)#do sho ip int brief

Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES TFTP up up
FastEthernet0/0.1 unassigned YES manual up up
Test_Router(config-subif)#

Notice that you will not actually have an I.P address applied

................................................................................................

Now using the correct order:

Test_Router(config)#int f0/0
Test_Router(config-if)#no shut
Test_Router(config-if)#int f0/0.1
Test_Router(config-subif)#encaps dot1q 1
Test_Router(config-subif)#ip add 192.168.1.254 255.255.255.0
Test_Router(config-subif)#do sho ip int brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES TFTP up up
FastEthernet0/0.1 192.168.1.254 YES manual up up
Test_Router(config-subif)#
No error message and all is good

pham0329

billyr wrote: »

bangs head on wall!!!

Of course you can enter the Encaps command afterwards, that's what the error message is telling you to do, it is telling you, you were missing the encaps command, that is why you had an error message in the first place. It now requires you to enter the encapsulation. However when you do so, you will find that your I.P address wouldn't have taken effect.

Bangs head on wall even harder!!!

You're contradicting yourself.

The reason the command was invalid and not showing in IOS help is that he was trying to apply the command in the wrong order.

Of course you can enter the Encaps command afterwards

xirtlook

IB4TL.

so is it resolved yet? that was my first thought, was that the port/interface had to be setup with the correct encapsulation.
if any command was missing, I would assume its due to the IOS version.

abst2act

Monkerz wrote: »

This isn't youtube, ebaumsworld, or any other site where trolling is tolerated. If you have nothing nice to say, say nothing at all.

How am I trolling when I created this thread and was simply seeking for help? Who wouldn't get upset after someone just insulted you with a remark that neither provides a positive or constructive feedback.

abst2act

billyr wrote: »

bangs head on wall!!!

Of course you can enter the Encaps command afterwards, that's what the error message is telling you to do, it is telling you, you were missing the encaps command, that is why you had an error message in the first place. It now requires you to enter the encapsulation. However when you do so, you will find that your I.P address wouldn't have taken effect.

However if you configure it in the correct order you won't have any error message.

Check below:

Example 1 using the incorrect method:

est_Router(config)#int f0/0
Test_Router(config-if)#no shut
Test_Router(config-if)#int f0/0.1
Test_Router(config-subif)#ip add 192.168.1.254 255.255.255.0

% Configuring IP routing on a LAN subinterface is only allowed if that
subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q,
or ISL vLAN.
Test_Router(config-subif)#encaps dot1q 1
Test_Router(config-subif)#do sho ip int brief

Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES TFTP up up
FastEthernet0/0.1 unassigned YES manual up up
Test_Router(config-subif)#

Notice that you will not actually have an I.P address applied

................................................................................................

Now using the correct order:

Test_Router(config)#int f0/0
Test_Router(config-if)#no shut
Test_Router(config-if)#int f0/0.1
Test_Router(config-subif)#encaps dot1q 1
Test_Router(config-subif)#ip add 192.168.1.254 255.255.255.0
Test_Router(config-subif)#do sho ip int brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES TFTP up up
FastEthernet0/0.1 192.168.1.254 YES manual up up
Test_Router(config-subif)#
No error message and all is good

I appreciate the reply. If I recall, it didn't matter which order I applied the command encaps dot1q 20. For some odd reason it just didn't recognize that encapsulation was a valid command. That lab I'm working on is in another location so I'll provide captures of the order you recommended.

billyr

pham0329 wrote: »

Bangs head on wall even harder!!!

You're contradicting yourself.

My apologies you are correct, after a fresh look, I realise I was arguing about the correct order of applying the command rather than the original fault.

Would be interested to see though, that as it shows the correct error message you would expect to see, whether when applying the commands in the correct order that made a difference.

edit: never mind, I see my query is already answered above.

abst2act

R2#sh ver
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-IO3-M), Version 12.3(19), RELEASE SOFTWARE (fc2)
Technical Support: [URL="http://www.cisco.com/techsupport"]Support and Documentation - Cisco Systems[/URL]
Copyright (c) 1986-2006 by cisco Systems, Inc.
Compiled Fri 12-May-06 04:13 by evmiller
Image text-base: 0x80008098, data-base: 0x80D61D98


ROM: System Bootstrap, Version 11.3(2)XA3, PLATFORM SPECIFIC RELEASE SOFTWARE (f
c1)
ROM: C2600 Software (C2600-IO3-M), Version 12.3(19), RELEASE SOFTWARE (fc2)


R2 uptime is 1 day, 4 minutes
System returned to ROM by power-on
System image file is "flash:c2600-io3-mz.123-19"


cisco 2620 (MPC860) processor (revision 0x100) with 28672K/4096K bytes of memory
.
Processor board ID JAB030507Q7 (1171260723)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
1 FastEthernet/IEEE 802.3 interface(s)
2 Serial network interface(s)
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read/Write)


Configuration register is 0x2102


R2#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
R2(config)#int f0/0.10
R2(config-subif)#encapsulation dot1q 10
                  ^
% Invalid input detected at '^' marker.


R2(config-subif)#?
Interface configuration commands:
  arp             Set arp type (arpa, probe, snap) or timeout
  backup          Modify backup parameters
  bandwidth       Set bandwidth informational parameter
  bgp-policy      Apply policy propagated by bgp community string
  bridge-group    Transparent bridging interface parameters
  cdp             CDP interface subcommands
  default         Set a command to its defaults
  delay           Specify interface throughput delay
  description     Interface specific description
  exit            Exit from interface configuration mode
  glbp            Gateway Load Balancing Protocol interface commands
  ip              Interface Internet Protocol config commands
  keepalive       Enable keepalive
  llc2            LLC2 Interface Subcommands
  mtu             Set the interface Maximum Transmission Unit (MTU)
  netbios         Use a defined NETBIOS access list or enable name-caching
  no              Negate a command or set its defaults
  ntp             Configure NTP
  rate-limit      Rate Limit
  service-policy  Configure QoS Service Policy
  shutdown        Shutdown the selected interface
  snapshot        Configure snapshot support on the interface
  snmp            Modify SNMP interface parameters
  standby         HSRP interface configuration commands
  timeout         Define timeout values for this interface
  traffic-shape   Enable Traffic Shaping on an Interface or Sub-Interface
  vrrp            VRRP Interface configuration commands


R2(config-subif)#ip address 192.168.10.1 255.255.255.0


% Configuring IP routing on a LAN subinterface is only allowed if that
subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q,
or ISL vLAN.


R2(config-subif)#encapsulation dot1q 10
                  ^
% Invalid input detected at '^' marker.


R2(config-subif)#

So as you can see running version 12.3 doesn't allow me to configure a subinterface with an IP address regardless of the order I set the encapsulation.

KrisA

abst2act wrote: »

So as you can see running version 12.3 doesn't allow me to configure a subinterface with an IP address regardless of the order I set the encapsulation.

So I am trying to improve my tshooting abilities for Cisco and I want to make sure that I understand the issue. Your missing the IP PLUS Feature set correct?

abst2act

KrisA wrote: »

So I am trying to improve my tshooting abilities for Cisco and I want to make sure that I understand the issue. Your missing the IP PLUS Feature set correct?

Hey KrisA, that is correct. I was thinking since I have a router with ver 12.4 if I could copy the IOS image via TFTP and flash it on the router running the old IOS.

KrisA

abst2act wrote: »

Hey KrisA, that is correct. I was thinking since I have a router with ver 12.4 if I could copy the IOS image via TFTP and flash it on the router running the old IOS.

As long as you have the memory for it. (to lazy to look up the size of 12.4) .. Curious to how this will turn out and following

gramacorp

If there isnt enough room in flash for the new ios you can boot from a tftp server