Switching

Interesting Mac Address Flap issue

Hello all, I have an interesting little mac address flapping issue. To set this up I will explain how the network is set up. Basically it is a hub and spoke with each access switch having two trunks back to the core. Spanning tree is blocking on one ...

Resolved! QSFP to 4x SFP cable (e.g. QSFP-4X10G-AC7M)

Hi, if i connect such a cable / module to my Nexus 3064-T, will there be 4 configurable 10G interfaces on the Nexus side? Would it be possible to connect 4 different devices with a cable like this? Best regards, Mark

Stacking issues between

We have currently a stack of 2 switches in production. ***************************************************************************** WS-C3750G-48TS 12.2(35)SE5 C3750-IPBASE-MWS-C3750G-48TS 12.2(35)SE5 C3750-IPBASE-M **********************************...

Resolved! Static Route through VPN

I can't seem to get a static route configured through a VPN. I need to allow a remote site to communicate with a WLC that is across a VPN link and behind a router. I can ping from a workstation at the branch office to the router in question but not...

DHCP Snooping and Duplicate Address Messages From Clients

Hi, I've configured DHCP snooping on all of our User switches (3750X, 3850s). It works well , but there have been a couple fluky behaviors. One issue, and I can't be sure it is caused by the snooping, is a duplicate address error on laptops. but I'v...

Plugging in CISCO GLC-T 1000BASE-T SFP TRANSCEIVER MODULE 30-1410-02 into a Catalyst 3750 Switch Gigabit Port

Hi All, I hope a very quick and simple question. Do I need to power down my Catalyst 3750 Network Switch to plug in a SFP Transceiver Module Part #30-1410-02 into an empty Gigabit Port or can I pull into the switch on the fly? The switch is up and ...

Switch reboot continuously

Hello, I have a switch Model: WS-C3750-48PS-SIOS version: c3750-ipbasek9-mz.122-55.SE10.bin It continuosly resets. I downgrade to c3750-ipbasek9-mz.122-35.SE5.bin and stops the reboot. The equipment works properly Anyone have any idea why this happe...

POE Switches vs Non POE Devices

hi, since we installed our new POE switches in different point of services (C2960X Software (C2960X-UNIVERSALK9-M), Version 15.0 (2) EX5).Sometimes power is discovered on non POE devices..And do a reset on the interface..Generally these devices are U...

STP Loopback error and Keepalive : ETHCNTR-3-LOOP_BACK_DETECTED

Hi everyone, a week ago a strange behavior happened on my network where an STP loop occured on two different spanning-tree vlan instances causing the isolation of 4 switchs at the same time (errdisable). Here's the log on PSW01, PSW02, BSW01, BSW02 (...

no LACP on cisco WS-C4507R

Hi, I am trying to turn on LACP on an old switch (WS-C4507R). However, there is no active/passive options available. SW1_((config-if)#channel-group 1 mode ? auto Enable PAgP only if a PAgP device is detected desirable Enable PAgP unconditionally o...

speed/duplex clarification in cisco 2611 router.

Hi, We have a cisco 2611 router for which I was trying to set the speed/duplex to 100/full, I am able to execute command as full-duplex over the interface Ethernet0/1 but could not set the speed to 100 as the command speed itselves is not able to g...

Resolved! Cisco 6509-E (sup720-3B) IOS upgrade from 12.2(18)SXF18 to 12.2(33)SXI14

FolksWe will be upgrading the following switches2 x 6509-E with SUP720-3B running IOS 12.2(33)SXJ11 x 6509-E with SUP720-3B running IOS 12.2(18)SFX8 1 x 6509 with SUP720-3B running IOS 12.2(18)SFX8 (this switch will get replaced eventually with anoth...

Resolved! Do you need a Default gateway in VLANs?

Hi forum, I'm working on a Packet Tracer 3.4.1.2 Skills Integration Lab as shown in the attachments below When I was doing this exercise I noticed that a default-gateway is meant to be implemented. What is the purpose of assigning a default gateway ...

Bandwidth Issues - QoS Related?

We have been having some bandwidth issues ever since we transitioned to a new switching infrastructure using the same configs but enabling QoS. It seems nobody really knows what is going on currently. We have determined that our firewall is capabl...