Discuss Catalyst brand switches with peers and experts.
Showing results for 
Search instead for 
Did you mean: 

Get 20% off switches when you combine Cisco solutions


Forum Posts

We have a core 6509 routers and 3750 edge switches. We are getting this error of the 3750 occasional:%SPANTREE-2-LOOPGUARD_BLOCK: Loop guard blocking port Port-channel2 on VLAN0007%SPANTREE-2-LOOPGUARD_UNBLOCK: Loop guard unblocking port Port-channel...

Hi everyone,I need to configure 5 public servers in my LAN. The IP Private addres are:,, and My ISP give me 5 public IP´s interface configuration on cisco 2901 are:Inside: 192.168...

Hi,Are there issues with the auto upgrade feature for 3750X stacks, either historically or currently? Some people prefer to upgrade switch stacks manually by disconnectiong the stack cables and uprading code on each switch.  I've done the manual proc...

lcaruso by Level 6
  • 18 replies
  • 0 Helpful votes

There is an arp entry..But no port for the cooresponding MAC address?#sho ip arp Protocol  Address          Age (min)  Hardware Addr   Type   InterfaceInternet             4   001d.45e2.8d43  ARPA   Vlan200Rack20-L3-3750-12#s...

mikegrous by Level 3
  • 7 replies
  • 0 Helpful votes

hello, im new to ccna .please any expert help me in this sinario,router 1721 with one wic-1adsl ,i have adsl conection with irb static ip.the router connect with mannaged switch through a trunk port.the switch has 2 vlans one for the static IPs and t...

hmagdy088 by Level 1
  • 5 replies
  • 0 Helpful votes

I have 4507 switch and I got the error of fan sensor which is mention belowPower                                                                                    Fan             InlineSupply  Model No                     Type                    St...

hi,I have cisco 3825 as perimter router (facing ISP), i have 64 MB/S line speed and i want to increase it to 128 MB/S, does this router support this functionallity, is there any recomandations .thanks                 

HI,I have a single core switch 3750 connected to 2 asa's each having its own dedicated Internet circuit, so the asa's are not in failover mode.I have a dedicate demarc vlan to each asa and running eigrp on the 2 demarc interfaces + the asa with one p...

HelloI am a newbie to Cisco. I am trying to setup NAT with DHCP in our office on CISCO 819 router. I am having a problem with DHCP not assigning an IP on vlan1. I cannot figure out what i'm doing wrong. Below is my config and  debug from DHCP. Any he...

Hi,I got the Following Error log in my Core switch, need help to figure out what happend?May 13 16:25:38 MAL: %STANDBY-3-DUPADDR: Duplicate address on Vlan20, sourced by 0000.0c07.ac14May 13 16:25:51 MAL: %DUAL-5-NBRCHANGE: IPX-EIGRP ...

We currently have 1 6509 and 3 4507's setup as layer 3 switches with trunks between them. I am working to create layer 3 connections between them to cut down on broadcast traffic. I have configured new management vlans on each one because the managem...

venturas05 by Level 1
  • 34 replies
  • 0 Helpful votes