Switch-to-switch

How do I configure a Catalyst port switch to connect to another Catalyst port (uplink connection) and allow some VLANs to pass through that uplink ?

Hi Joseph,
Here is how you configure trunking
interface FastEthernet0/1
description Connection to SW1
power inline never
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport trunk allowed vlan 20,25,999
switchport mode trunk
speed 100
duplex full
power inline never - disabled POE on the port
switchport trunk encapsulation dot1q - sets the encapsulation to 802.1q
switchport trunk allowed vlan 20,25,999 - is the vlans allowed to trunk over this port
switchport mode trunk - sets the port to trunking mode.
speed 100 - sets the speed to 100mb, depending on your connection
duplex full - sets the connection to full duplex using a crossover cable.
switchport trunk native vlan 999 - this is a security feature to change the native vlan 1 to native vlan 999 for security reasons. This can be any vlan numbber. This is optional
Hope this helps, please rate.
Cheers,
Justin

Similar Messages

Switch to Switch Connection

Hi, for one project we are using HP 1910-24G-PoE (170W) Switch (JE008A) switch. There are total six nos. of switches at different floors, out of these six switches one switch is located in main server room.
My first question is can we use SFP port available on each of five switches & connect it to one fiber patch panel through different LIU's ?
Sencond question is can we covert these into cat6 (RJ45) again & connect it to 6th switch located in main server room?
Thanks.

Hi Shashikant,
I given few thought what could be issue and following are few of the guess
Switch to Switch should be connected with cross cable -- It is connected
Both the ports should have same speed and duplex setting -- It is shared and OK
Possible Layer-2 loop - Needs to verify for both switches- Need topology view (if these switches are connected to any other networking devices)
Output of show cdp nei
Output of show spanning-tree
Output of show vtp status
Shutdown interface and then no shut the interface. Check the logging message on both the switches.
With this certainly you would be in position to identify the close the problem.
With regards,
Shailesh

Switch to switch cross cable ?

Well yesterday i read in a cisco book saying that you should have a cross cable when connecting switch to switch & a straight cable when connecting workstation to a switch , but currently i have stright all through , switch to switch or switch to pc .
network seems to run fine, why is this ?
thanks

Hi Malutaru1234,
I think you have copied exactly the same lines from my first post without checking that Fasi74 had alraedy replied that he is having 1900 switch.
Also it is not necessary that he need to configure trunk between the 2 switches when connected via cross over cable becuase trunk is just to pass the information of more than 1 vlan. If you have single vlan in your network you can connect the 2 switches via access link also.
Regards,
Ankur

Disable portfast on switch-to-switch connection

Hi,
From http://www.cisco.com/en/US/customer/tech/tk389/tk621/technologies_configuration_example09186a008009467c.shtml, it says, "do not use portfast when you have switch-to-switch connection. In this case, the command can result in a loop."
For e.g. when someone connects a switch port(with portfast enabled) to another switch port(with portfast enabled)
1) can this scenario cause a loop even though the connection between these switch is only a single link?
2) If it does not cause a loop, what will happen? STP recalculation which causes a short network outage?
Thanks.
Christina

Hi Christina,
1) Only if there is a redundant physical path between the switches, such as through another switch. If the only physical path between the two switches is the switch-to-switch link in question, then no loop can occur.
2) Portfast simply ignores the standard STP state transitions and immediately enters the forwarding state, so assuming no loop, a switch-to-switch link that has portfast configured will skip the 50 second STP convergence time and immediately forward traffic.
HTH,
Bobby
*Please rate helpful posts.

Cisco 4500X + VSS + Trust Sec Switch to Switch Encryption

Hi,
actually im testing and evaluationg the Cisco 4500X switch as new distribution switch for our Company.... Now i have some issues with one of our requirements.
For security reasons i need to encrypt the links between the 4500X and the access switches in other buildings (no issue with Trust Sec)
But ... now i also need to encrypt the link between the two 4500X if i run VSS ... my question is .. is it possible to encrypt the VSL link with TrustSec Switch to Switch encryption?
BR,
Florian

Hi Frloian,
If you have 2 switches in different data centers than you do not need VSS. In fact this is very bad design as the whole concept of VSS is grasped on dual home design. In the essence the proper design of VSS system is to have every downsteram switch connected with one link to one VSS switch and other link to second VSS switch, so that when one VSS switch would fail other can take over. Please look at the VSS best practises:
http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6500-virtual-switching-system-1440/109547-vss-best-practices.html#vss_best
Update:
There is possibility to encrypt VSL link, but only in 6500 sup2t environment:
http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/15-0SY/configuration/guide/15_0_sy_swcg/virtual_switching_systems.html#wp1341144

Can I switch License switch from PC to mac? AE cs5

Can I switch License switch from PC to mac? AE cs5

Platform swaps only apply to current versions. You need to upgrade to CS6 and make the switch.
http://kb2.adobe.com/cps/405/kb405819.html
Mylenium

Conflict using simultaneously IVI Switch and Switch Executive ?

Hi,
I use IVI Switch and Switch Executive libraries in an Labwindows CVI project, and I meet some problems :
I call SE lib for InitSession/CloseSession/FindRoute and Connect/Disconnect (apply to any switch devices in the SE configuration).
I call IVI Switch lib for SelfTest and Reset (apply to a single device).
But when I do an IVI Switch Reset then a Switch Executive Connect or Disconnect, an error occurs : Switch Executive seems to ignore what IVI Switch operations do to the device ?
Also, can you tell me if :
niSE_OpenSession performs a self test for the devices in the config ? A reset ?
niSE_CloseSession performs a reset for the devices in the config ?
Thanks.

Hello,
the niSE session talks to underlying IVI drivers using the IVI Switch session underneath, so any additional opening of IVI Switch session to the same device will cause the two driver sessions (that keep the information about the state of the hardware connections) to be either one or both out of synch with the actual hardware state). Because of the architecture of the underlying IVI drivers, niSE session cannot know if and what someone did to the instrument using IVI Switch session.
Therefore, it is not adviseable to use IVI Switch session while having another session open to the same device. If you need to use the invasive operations - which is anything that changes the state of the device, such as Reset and possibly self-test (self-test may be implemented as an operation that cycles relays and it may not but you can't be sure), you must make sure that one session is open and closed before another type of session is open.
The ni Switch Executive Open Session calls IviSwtch_init (with ID Query and Reset set to true) and CloseSession closes the IVI Switch sessions with the call to Close. The niSE session does not make calls to either reset or self-test explicitly.
Always attempt to perform all the operations on the same piece of hardware using the same API. If you need to reset switches, use the niSE_DisconnectAll function. If you need to perform the self-test operation, open a session to IVI Switch and perform the self-test, and then close it before opening the session to niSE virtual device.
There is also a back-door possibility that you can obtain the IVI Switch session that has been open for the constituent devices by niSE, but you must make sure that whatever you do with that session leaves the state of the switch intact when you get back to making calls to the niSE session. If unsure, you can always call niSE_DisconnectAll() as the first thing coming back to the niSE session to ensure that the state stored in niSE session matches the state on the actual hardware.
Again, it is best not to use both sessions, but rather pick one and try to perform all operations with it before switching to another type of session.
Srdan Zirojevic

How to switch between switches in CLI

Hello,
I have 3 2524's stacked. When I go into CLI mode (telnet) - on the very begining I am asked to choose what switch shoudl I select ..... After selecting, how can I choose other switch without logging out and logging in again ?
Thank you.

Follow the directions here:
http://support.apple.com/kb/ht1311

[QEMU/KVM] Use KVM switch to switch mouse/kayboard between host and VM

I finally have my QEMU/KVM setup running and working as I want it, except for one thing. I have a KVM switch (a piece of hardware not the hypervisor ) to switch audio and video. It also offers the feature to switch mouse/keyboard between to Computers. Here is the relevant excerpt from my lsusb:
Bus 002 Device 048: ID 046d:c52b Logitech, Inc. Unifying Receiver
Bus 002 Device 047: ID 0557:8021 ATEN International Co., Ltd CS1764A [CubiQ DVI KVMP Switch]
Bus 002 Device 046: ID 046d:c52b Logitech, Inc. Unifying Receiver
Bus 002 Device 045: ID 0557:8021 ATEN International Co., Ltd CS1764A [CubiQ DVI KVMP Switch]
The device named "Logitech, Inc. Unifying Receiver" is the dongle for my mouse and keyboard. The first problem is that both devices (in both states of the switch they both appear) have the same device id 046d:c52b. This can be solved by telling qemu to identify the device by #bus.#device instead of the id. The problem is that after each switching the device number increases. This makes sense as for the system the switching process is as if the device was unplugged and plugged in in a different usb port. Therefore the device would probably be disconnected from the VM when it was assigned on the VM's startup (is there a way to add usb devices on the fly to a vm without typing an add_usb command in the qemu shell). Do you have any ideas what I could do?
EDIT: Just found about QMP. Would it be possible to save an initial condition (mouse/keyboard is on host) and fetch new devices busses after switching (udev?) and switch the saved sate? If the state is now "m/k should be on the vm" one could send qemu an adequate add command.
EDIT2: I found out that my mainboard's usb is organized using 3 usb controllers (2x2.0, 1x3.0 each with 4 ports). I want to pass one of those PCI controllers to the VM but all I get is a black screen.
EDIT3: I tried the other usb controller and it worked. Well, kind of. I moved the mouse in a circle and made a right click. Than I was not able to use the mouse or the keyboard anymore. Should I consider buying a PCI USB2.0 controller as that might be easier to forward?
Last edited by fkoehler (2015-04-29 23:50:07)

This article has someinteresting information in the comments. You don't have to use a kvm switch neccessarily. I for one prefer a software solution.
Okay, so to make things clear: I do not switch keyboard/mouse. I keep them shared between both OS, using Synergy. The host OS runs a web server, and the guest OS runs a client – they exchange mouse position information, so that at any time only one of them receives ‘clicks’. This is great for both multi- and single-monitor setups.
Another story is that I have two video outputs connected to a single monitor, and I would like to switch between them without using the buttons on the monitor itself. For this, I use the I2C that is embedded within HDMI or DP.
Almost all monitors support DDC, but there are scarce apps that can make us of it. There is DDCcontrol for linux, but it is completely outdated, and failed to work with my particular monitor. So I ended up getting to know the VESA DDC standard, reading the source of that tool and several similar ones, and created a simple C program (source) that works in case of my setup. Most likely it will not work elsewhere, but it should give you a nice starting point for communicating with the monitor. The fragile spots are line 41 – you may need to change the i2c bus number the the one correct for your system, and you may need to prepare other data to send to the monitor (68 and 71) if you want to switch between other outputs than I do. Refer to the standard in order to prepare them.
As for how to change his source code to help you, I am not of much help right now as I do not know the DDC protocol. Hope that helps.
Last edited by noctlos (2015-04-30 16:01:45)

Locally Switched / Centrally Switched on Flex Connect AP

Hi All,
Scenario (is this possible)
I have HQ Site (Site A) -with the WLC
I have a remote site (Site B) with one AP.
Site A has Internet Breakout. Site B doesn't
Is it possible with this one AP to have Multiple SSIDs, some of which are switched locally at the remote site and some which are switched centrally back at the HQ?
E.G I want to have SSID for the data vlan at Site B. Any Laptop connecting to this is dropped onto the Data VLAN.
I also want to have a GUEST SSID for Internet but have this traffic be tunneled back to HQ and use Internet Breakout there.
Is this possible?
Thanks

On the advanced tab of the WLAN you can enable that SSID for FC Local Switching. The AP then needs to be in Flexconnect mode. You then go to the FC tab of the AP and define the local VLANs for the locally switched WLANs. There will be 2 lists of SSIDs, locally switched and centrally switched. Obviously you don't define VLANs for the centrally switched WLANs.
Whatever you define on the AP will overwrite the interface on the WLC.
AP Groups and FC Groups are not needed.

Using Cisco MDS 9148 switch for switching and routing

Hi Gurus,
Can you please advice me! Can i configure interface trunking, routing and dhcp services on the Cisco MDS 9148 switch?
Thanks for your response!!

Tommy,
MDS9148 is a Storage SAN Fibre Channel switch, it doesn't support Ethernet, IP, VLANs, VLAN trunking, 802.1Q, IP routing, DHCP. It's meant for Fibre Channel connectivity between Fibre Channel server HBAs and Fibre Channel storage.
Roman

Multicam switch is switching audio

I am trying to switch views on a couple of angles and the audio isn't cooperating.
I have two camera views and a separately recorded audio track for same. I created an in-sync multicam clip, no problem. However, now that I have that multicam clip in the timeline, when I switch between the two views I lose the good audio as soon as I make the cut.
I started by going to the clips multi-angle view in the viewer window and selected the good audio track. I clicked on the filmstrip icon to make it blue and the keyline around the audio icon turned green; as it should. I played back the clip and was able to switch views with the audio remaining from the good audio clip; the two video views now with a blue line around each thumbnail.
With the clip in the timeline I play the clip to where I want to switch views and hit "2" to switch to view 2. When I do, the audio to the left of the cut remains the good audio track, but to the right of the cut the audio switches to the scratch audio of the camera that shot that view. If I move forward in the clip and hit "1" to switch back to view 1, the audio switches to the recording from THAT camera. The good audio clip is rendered useless once the switch cut has been made, never to return.
I followed instructions to a "T" on making the multicam switch and I hope I describe it well enough above to illustrate that fact, but clearly something's not going right. Any clues?

This is the multiclip dropped onto the timeline:
This is the timeline after cutting from "view_A" to "view_B." As you can see, a drastic change in the waveform:
This is the timeline after switching view back to "view_A." A less-drastic change in the waveform but its subtlety shows that neither has it returned to the high-quality audio but instead to the camera's onboard audio:

Activating switch in switch framework is client dependent?

Hi Experts,
We have an interesting scenario where a system is running in 2 clients in the same server. Now the requriement is to activate few of the switches in only one client. Is this possible?
I am not really really sure on which forum to post this thread. Now that I am an ABAPer finally ended up here.
Regards,
Arun.

Hi Arun,
There is a method. But I'm not sure if this is should be done or if this is right.
@moderators, Experts Please correct me if i'm wrong.
Go to T.code SFW1
Go to your corresponding switch.
Click on Global status.
It shows a description for each client.
Regards
ncvajja

Spanning tree STG from switch to switch

Does the STG need to match on all linked switches for VLANs to function properly using PVRST? It seems like whenever I notice they are not the same the VLANs that are not the same are not working as they should be.

Hello,
A couple of comments on this topic. As noted, the STP instance to VLAN number is locally significant and generally does not need to match between switches. One exception to this is for switches in a vLAG pair (similar to Cisco vPC). For a pair of switches sharing a common vLAG tier ID, the STP-instance-to-VLAN-number must match exactly, or unexpected blocking/discarding will occur (I have never seen this cause a loop, just unexpected blocking, and one way to see if this is the case is to use the command “show span block” and look for any interfaces blocking that should not be). Lenovo switches use an algorithm to assign an instance to a VLAN, and if you add VLANs in the same order on a pair of switches, those VLANs will get the same STP instance. But if you add VLANs in different order on each switch, then they might get a different instance assigned, and then would require manually adjustment on a vLAG pair. Again, this does not matter on non-vLAGed switches, and can be any instance, but as noted in a previous response, it is always a good idea to have them in sync between switches, just to prevent user confusion.
There is also a draft paper out for Lenovo switching best practices at the following link that covers a lot of such topics:
http://www.redbooks.ibm.com/abstracts/sg248245.html?Open
Thanks, Matt

Switch in switch??

Is it bad code style to make a switch inside a switch??
public void test(int a, int b){
switch(a){
     case 1:
           switch(b){
               case 1:
               //Do things.
                    break;
            break;
       case 2:
            // Do things
             break;


Hardly a good example of encapsulation. I thought
polymorphism and runtime typing was supposed to make
such constructs rare.Polymorphism can be taken too far. Sometimes attributes of a single class are preferable to making subclasses. Like in this example:switch (anchor) {
case NORTH: {resultX += widthDiff/2; break;}
case NORTH_EAST: {resultX += widthDiff; break;}
case EAST: {resultX += widthDiff; resultY += heightDiff/2; break;}
case SOUTH_EAST: {resultX += widthDiff; resultY += heightDiff; break;}
case SOUTH: {resultX += widthDiff/2; resultY += heightDiff; break;}
case SOUTH_WEST: {resultY += heightDiff; break;}
case WEST: {resultY += heightDiff/2; break;}
case NORTH_WEST: {break;}
case CENTER: {resultX += widthDiff/2; resultY += heightDiff/2; break;}
}It really doesn't want to be converted into nine different subclasses with overriding applyAnchor() methods.
I couldn't find any examples of my code that nested a switch inside a switch. Normally I don't object to nesting structures (I am pretty sure that somewhere I have an anonymous inner class nested inside another anonymous inner class), but since I dislike the switch statement that's probably the only reason I don't have nested switches.

Switch-to-switch

Similar Messages

Maybe you are looking for