VLANs, trunking and dot1q questions

Discussion in 'Cisco' started by Chris, Jan 30, 2007.

  1. Chris

    Chris Guest

    I've been wrangling with connecting a Catalyst 4006 (running CatOS) to
    a Cisco GbESM switch module (running IOS) in an IBM BladeCenter.

    One area in which I'm still not sure how everything "fits together" is
    in terms of VLANs (native and not), trunking and 802.1q. The problems
    stem from the way the GbESM modules in the BladeCenters are setup, but
    I'm temporarily unable to change how they work. Specifically, the
    GbESM ships with it's management ports in VLAN 1 and all other ports
    in VLAN 2. Unfortunately for me, all the ports on my Catalyst 4006 are
    in VLAN 1.

    If I don't set dot1q to "off", I get this when (in CatOS) when I try
    and connect the GbESM to the Catalyst:

    CAT4000-1> (enable) sh port 4/20
    * = Configured MAC Address

    Port Name Status Vlan Level Duplex Speed
    Type
    ----- ------------------ ---------- ---------- ------ ------ -----
    ------------
    4/20 connected trunk normal a-full a-1Gb
    10/100/1000

    Note that the VLAN status is "trunk". In this example, if the VLAN
    status is "trunk", I am unable to pass any data to the BladeCenter --
    I presume that it's expecting traffic on VLAN 2, and it's only
    receiving traffic on VLAN 1 (which is what the 4006 has all of its
    ports in) so it's not receiving any data. However, if I turn off dot1q
    (using this command: set trunk 4/20 off dot1q 1-1005,1025-4094), on
    the port connecting the two switches, I get this:

    CAT4000-1> (enable) sh port 4/20
    * = Configured MAC Address

    Port Name Status Vlan Level Duplex Speed
    Type
    ----- ------------------ ---------- ---------- ------ ------ -----
    ------------
    4/20 connected 1 normal a-full a-1Gb
    10/100/1000

    And now everything works fine. My question is, what exactly is the
    "set trunk 4/20 off dot1q 1-1005,1025-4094" command accomplishing?
    >From CatOS, I can see this warning: "2007 Jan 30 07:00:33 EST -05:00

    %CDP-4-NVLANMISMATCH:Native vlan mismatch detected on port 4/20". Am I
    to presume that the dot1q command effectively tells the 4006 to ignore
    the VLANs that it's seeing, and just pretend everything is in VLAN 1?
    I suppose my ultimate question is, why does it work this way but no
    others?

    I have a reasonable idea of how VLANs work, but when it comes to
    trunking and 802.1q I fear that I am getting a little lost. Any
    replies helping to clarify this would be, by me, appreciated!

    TIA and HAND,


    Chris
    Chris, Jan 30, 2007
    #1
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  2. Chris

    Jun Guest

    Hello Chris ,
    I'm jun from Japan
    I set up a GbESM switch modulein an IBM BladeCenter H today.
    I study them a little and hava an idea.

    Probably,
    Catalyst 4006 send VLAN info to BladeCenter as Vlan 1,
    GbESM external port drop all data belonging to Vlan1, because vlan 1 is used
    for management
    module.
    By setting dot1q to "off", 4006 will not send VLAN info with data.
    If GbESM recieved that data which don't have Vlan info, GbESM add Vlan info
    to Vlan2.
    (external port was set to access vlan 2)
    so connection can be established.

    Probably





    "Chris" <> wrote in message
    news:...
    > I've been wrangling with connecting a Catalyst 4006 (running CatOS) to
    > a Cisco GbESM switch module (running IOS) in an IBM BladeCenter.
    >
    > One area in which I'm still not sure how everything "fits together" is
    > in terms of VLANs (native and not), trunking and 802.1q. The problems
    > stem from the way the GbESM modules in the BladeCenters are setup, but
    > I'm temporarily unable to change how they work. Specifically, the
    > GbESM ships with it's management ports in VLAN 1 and all other ports
    > in VLAN 2. Unfortunately for me, all the ports on my Catalyst 4006 are
    > in VLAN 1.
    >
    > If I don't set dot1q to "off", I get this when (in CatOS) when I try
    > and connect the GbESM to the Catalyst:
    >
    > CAT4000-1> (enable) sh port 4/20
    > * = Configured MAC Address
    >
    > Port Name Status Vlan Level Duplex Speed
    > Type
    > ----- ------------------ ---------- ---------- ------ ------ -----
    > ------------
    > 4/20 connected trunk normal a-full a-1Gb
    > 10/100/1000
    >
    > Note that the VLAN status is "trunk". In this example, if the VLAN
    > status is "trunk", I am unable to pass any data to the BladeCenter --
    > I presume that it's expecting traffic on VLAN 2, and it's only
    > receiving traffic on VLAN 1 (which is what the 4006 has all of its
    > ports in) so it's not receiving any data. However, if I turn off dot1q
    > (using this command: set trunk 4/20 off dot1q 1-1005,1025-4094), on
    > the port connecting the two switches, I get this:
    >
    > CAT4000-1> (enable) sh port 4/20
    > * = Configured MAC Address
    >
    > Port Name Status Vlan Level Duplex Speed
    > Type
    > ----- ------------------ ---------- ---------- ------ ------ -----
    > ------------
    > 4/20 connected 1 normal a-full a-1Gb
    > 10/100/1000
    >
    > And now everything works fine. My question is, what exactly is the
    > "set trunk 4/20 off dot1q 1-1005,1025-4094" command accomplishing?
    > >From CatOS, I can see this warning: "2007 Jan 30 07:00:33 EST -05:00

    > %CDP-4-NVLANMISMATCH:Native vlan mismatch detected on port 4/20". Am I
    > to presume that the dot1q command effectively tells the 4006 to ignore
    > the VLANs that it's seeing, and just pretend everything is in VLAN 1?
    > I suppose my ultimate question is, why does it work this way but no
    > others?
    >
    > I have a reasonable idea of how VLANs work, but when it comes to
    > trunking and 802.1q I fear that I am getting a little lost. Any
    > replies helping to clarify this would be, by me, appreciated!
    >
    > TIA and HAND,
    >
    >
    > Chris
    >
    Jun, Jan 30, 2007
    #2
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  3. Chris

    Chris Guest

    On Jan 30, 8:01 am, "Jun" <> wrote:
    > Hello Chris ,
    > I'm jun from Japan
    > I set up a GbESM switch modulein an IBM BladeCenter H today.
    > I study them a little and hava an idea.
    >
    > Probably,
    > Catalyst 4006 send VLAN info to BladeCenter as Vlan 1,
    > GbESM external port drop all data belonging to Vlan1, because vlan 1 is used
    > for management
    > module.
    > By setting dot1q to "off", 4006 will not send VLAN info with data.
    > If GbESM recieved that data which don't have Vlan info, GbESM add Vlan info
    > to Vlan2.
    > (external port was set to access vlan 2)
    > so connection can be established.


    Arigato gozaimasu Jun! How have you connected your GbESM, do you have
    the ports in VLAN 1 or VLAN 2? I would like all ports to be in the
    same VLAN, but I do not know if it is possible. :-(


    Chris

    >
    > Probably
    >
    > "Chris" <> wrote in messagenews:...
    >
    > > I've been wrangling with connecting a Catalyst 4006 (running CatOS) to
    > > a Cisco GbESM switch module (running IOS) in an IBM BladeCenter.

    >
    > > One area in which I'm still not sure how everything "fits together" is
    > > in terms of VLANs (native and not), trunking and 802.1q. The problems
    > > stem from the way the GbESM modules in the BladeCenters are setup, but
    > > I'm temporarily unable to change how they work. Specifically, the
    > > GbESM ships with it's management ports in VLAN 1 and all other ports
    > > in VLAN 2. Unfortunately for me, all the ports on my Catalyst 4006 are
    > > in VLAN 1.

    >
    > > If I don't set dot1q to "off", I get this when (in CatOS) when I try
    > > and connect the GbESM to the Catalyst:

    >
    > > CAT4000-1> (enable) sh port 4/20
    > > * = Configured MAC Address

    >
    > > Port Name Status Vlan Level Duplex Speed
    > > Type
    > > ----- ------------------ ---------- ---------- ------ ------ -----
    > > ------------
    > > 4/20 connected trunk normal a-full a-1Gb
    > > 10/100/1000

    >
    > > Note that the VLAN status is "trunk". In this example, if the VLAN
    > > status is "trunk", I am unable to pass any data to the BladeCenter --
    > > I presume that it's expecting traffic on VLAN 2, and it's only
    > > receiving traffic on VLAN 1 (which is what the 4006 has all of its
    > > ports in) so it's not receiving any data. However, if I turn off dot1q
    > > (using this command: set trunk 4/20 off dot1q 1-1005,1025-4094), on
    > > the port connecting the two switches, I get this:

    >
    > > CAT4000-1> (enable) sh port 4/20
    > > * = Configured MAC Address

    >
    > > Port Name Status Vlan Level Duplex Speed
    > > Type
    > > ----- ------------------ ---------- ---------- ------ ------ -----
    > > ------------
    > > 4/20 connected 1 normal a-full a-1Gb
    > > 10/100/1000

    >
    > > And now everything works fine. My question is, what exactly is the
    > > "set trunk 4/20 off dot1q 1-1005,1025-4094" command accomplishing?
    > > >From CatOS, I can see this warning: "2007 Jan 30 07:00:33 EST -05:00

    > > %CDP-4-NVLANMISMATCH:Native vlan mismatch detected on port 4/20". Am I
    > > to presume that the dot1q command effectively tells the 4006 to ignore
    > > the VLANs that it's seeing, and just pretend everything is in VLAN 1?
    > > I suppose my ultimate question is, why does it work this way but no
    > > others?

    >
    > > I have a reasonable idea of how VLANs work, but when it comes to
    > > trunking and 802.1q I fear that I am getting a little lost. Any
    > > replies helping to clarify this would be, by me, appreciated!

    >
    > > TIA and HAND,

    >
    > > Chris
    Chris, Jan 30, 2007
    #3
  4. Chris

    Jun Guest

    Hi Chris,

    I'm not sure this is your question.
    my English problem
    I setup GbESM via the management module (192.168.70.125 default )
    Management module's web interface have a web interface and telnet session to
    GbESM
    It is not able to access GbESM via External port by default .
    Workaround is create another VLAN ( ex VLAN 10)
    Give the ip address to the VLAN 10,so we can access to GbESM via external
    port.


    "Chris" <> wrote in message
    news:...
    > On Jan 30, 8:01 am, "Jun" <> wrote:
    > > Hello Chris ,
    > > I'm jun from Japan
    > > I set up a GbESM switch modulein an IBM BladeCenter H today.
    > > I study them a little and hava an idea.
    > >
    > > Probably,
    > > Catalyst 4006 send VLAN info to BladeCenter as Vlan 1,
    > > GbESM external port drop all data belonging to Vlan1, because vlan 1 is

    used
    > > for management
    > > module.
    > > By setting dot1q to "off", 4006 will not send VLAN info with data.
    > > If GbESM recieved that data which don't have Vlan info, GbESM add Vlan

    info
    > > to Vlan2.
    > > (external port was set to access vlan 2)
    > > so connection can be established.

    >
    > Arigato gozaimasu Jun! How have you connected your GbESM, do you have
    > the ports in VLAN 1 or VLAN 2? I would like all ports to be in the
    > same VLAN, but I do not know if it is possible. :-(
    >
    >
    > Chris
    >
    > >
    > > Probably
    > >
    > > "Chris" <> wrote in

    messagenews:...
    > >
    > > > I've been wrangling with connecting a Catalyst 4006 (running CatOS) to
    > > > a Cisco GbESM switch module (running IOS) in an IBM BladeCenter.

    > >
    > > > One area in which I'm still not sure how everything "fits together" is
    > > > in terms of VLANs (native and not), trunking and 802.1q. The problems
    > > > stem from the way the GbESM modules in the BladeCenters are setup, but
    > > > I'm temporarily unable to change how they work. Specifically, the
    > > > GbESM ships with it's management ports in VLAN 1 and all other ports
    > > > in VLAN 2. Unfortunately for me, all the ports on my Catalyst 4006 are
    > > > in VLAN 1.

    > >
    > > > If I don't set dot1q to "off", I get this when (in CatOS) when I try
    > > > and connect the GbESM to the Catalyst:

    > >
    > > > CAT4000-1> (enable) sh port 4/20
    > > > * = Configured MAC Address

    > >
    > > > Port Name Status Vlan Level Duplex Speed
    > > > Type
    > > > ----- ------------------ ---------- ---------- ------ ------ -----
    > > > ------------
    > > > 4/20 connected trunk normal a-full a-1Gb
    > > > 10/100/1000

    > >
    > > > Note that the VLAN status is "trunk". In this example, if the VLAN
    > > > status is "trunk", I am unable to pass any data to the BladeCenter --
    > > > I presume that it's expecting traffic on VLAN 2, and it's only
    > > > receiving traffic on VLAN 1 (which is what the 4006 has all of its
    > > > ports in) so it's not receiving any data. However, if I turn off dot1q
    > > > (using this command: set trunk 4/20 off dot1q 1-1005,1025-4094), on
    > > > the port connecting the two switches, I get this:

    > >
    > > > CAT4000-1> (enable) sh port 4/20
    > > > * = Configured MAC Address

    > >
    > > > Port Name Status Vlan Level Duplex Speed
    > > > Type
    > > > ----- ------------------ ---------- ---------- ------ ------ -----
    > > > ------------
    > > > 4/20 connected 1 normal a-full a-1Gb
    > > > 10/100/1000

    > >
    > > > And now everything works fine. My question is, what exactly is the
    > > > "set trunk 4/20 off dot1q 1-1005,1025-4094" command accomplishing?
    > > > >From CatOS, I can see this warning: "2007 Jan 30 07:00:33 EST -05:00
    > > > %CDP-4-NVLANMISMATCH:Native vlan mismatch detected on port 4/20". Am I
    > > > to presume that the dot1q command effectively tells the 4006 to ignore
    > > > the VLANs that it's seeing, and just pretend everything is in VLAN 1?
    > > > I suppose my ultimate question is, why does it work this way but no
    > > > others?

    > >
    > > > I have a reasonable idea of how VLANs work, but when it comes to
    > > > trunking and 802.1q I fear that I am getting a little lost. Any
    > > > replies helping to clarify this would be, by me, appreciated!

    > >
    > > > TIA and HAND,

    > >
    > > > Chris

    >
    Jun, Jan 30, 2007
    #4
  5. Chris

    Matt Slavin Guest

    Hi Chris,
    Long thread, and I'm not sure exactly where you are at on this. Did yo
    get your questions answered? There is an IBM red paper that might be o
    help with your questions at:
    http://www.redbooks.ibm.com/Redbooks.nsf/RedbookAbstracts/REDP3869.html
    Section 5.3 talks about how to select a management path for the IGES
    (recommend over the MM uplinks, NOT over the IGESM uplinks). Section
    discusses data connectivity for the IGESM uplinks, but does not includ
    connecting the IGESM to a CatOS device upstream (this can be done, bu
    you do have to understand the ways to do it, which would require mor
    information).
    Let me know if you’re still stuck and I will try to assist.
    Thanks, Mat

    --
    Matt Slavi
    -----------------------------------------------------------------------
    Matt Slavin's Profile: http://www.futurehardware.in/member.php?userid=72
    View this thread: http://www.futurehardware.in/showthread.php?t=56869

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    Matt Slavin, Jan 31, 2007
    #5
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