Skip to main content

Questions tagged [cisco-3750]

The Cisco Catalyst 3750 is a line of 1-RU switches by Cisco Systems.

Filter by
Sorted by
Tagged with
0 votes
2 answers
3k views

CDP Native VLAN Mismatch

I am getting CDP NATIVE VLAN MISMATCH logs on my Cisco 3750x switch stack. Gig 2/0/5 and Gig 4/0/6 are in no way physically connected to each other (neither is 1/0/44 and 2/0/13 as you'll see below). ...
Craken's user avatar
  • 681
3 votes
1 answer
3k views

Moving from 12.x IOS to 15.x IOS - Cisco 3750G

Is there any issue with jumping from IOS version 12.2(35)SE5 to 15.0.2-SE11 on a Cisco WS-C3750G-48PS-S switch? Should I upgrade to the latest 12.x first (12.2.55-SE12), and then move to the 15.x ...
Craken's user avatar
  • 681
2 votes
0 answers
203 views

Renumbering Cisco 3750X Stack

I am thinking about renumbering my Cisco 3750X stack. Currently as it sits, the stack from top to bottom is Switch 5 Switch 1 Switch 2 Switch 3 Switch 4 I am wanting the stack to be renumbered to ...
Craken's user avatar
  • 681
2 votes
1 answer
1k views

Scheduled reload Cisco 3750X Slot

I received a new Stackwise cable to make my switch stack of 5 Cisco 3750x's now fully redundant. Upon connecting the new Stackwise cable, I found that the switch did not recognize the new cable. I ...
Craken's user avatar
  • 681
5 votes
1 answer
1k views

Cisco DAI / arp inspection limit

During a recent penetration test it was found that we didn't have dai set quite as tight as possible to fully stop things. I'm running Cisco 3750x if it matters. The interfaces are configured with ...
Tim Brigham's user avatar
0 votes
1 answer
157 views

Static IP assignment 3750X - DHCP Override

I have a 3750X that I am running some testing with. I have a VLAN interface that is using 10.10.10.254/21 as it's primary IP and 192.168.10.254/24 as it's secondary IP. See below: interface Vlan10 ...
Craken's user avatar
  • 681
1 vote
1 answer
255 views

Migrating Configuration - 3750G to 3750X

What is the best practices to migrate configuration from an older Cisco switch model to a newer Cisco switch model? -I am not expecting to change any configuration, just simply want to be on the ...
Craken's user avatar
  • 681
2 votes
2 answers
3k views

Cisco 3750G - SSH Diffie Hellman Group 1 SHA1 Error

I recently implemented SSH configuration on my 3750G switch stack. I have -set the domain name -generated the rsa key using 2048 bits -ensured that the vty lines are set to transport input ssh Now ...
Craken's user avatar
  • 681
5 votes
2 answers
4k views

Should portfast be configured on the physical interfaces or on the logical port-channel, or both?

I'm using a Cisco 3750 switch and have two physical ports configured in a port channel that connects to a router. Should I configure spanning-tree portfast on the physical interfaces or on the port-...
slantalpha's user avatar
0 votes
2 answers
363 views

Multiple 802.1x clients, single port support on a Cisco 3750 switch?

I'm thinking of using our Cisco 3750 switch with our RADIUS server for 802.1x authentication on our Ethernet ports. If I enable 802.1x and a user connects a switch to their Ethernet jack, and the ...
slantalpha's user avatar
1 vote
2 answers
349 views

Cisco 3750X Switch stack best practices

I have a stack of 5 Cisco 3750Xs. I am debating between taking all my servers and putting them on one of the 5 switches, or distributing them over the first few ports of all 5 switches? All of the ...
Craken's user avatar
  • 681
6 votes
1 answer
3k views

Cisco 3750X Power Cable

I received a Cisco 3750X the other day. I went to go plug it in for testing and found that the standard three prong female power connector is no longer compatible with the power supply. Cisco has ...
Craken's user avatar
  • 681
0 votes
1 answer
723 views

Finding the IP address of a Cisco 3750G

Hello i have a Cisco 3750G switch and i need to find the IP address and I dont have a serial cable, so I need the IP address to login into the web-interface. Does it need to be connected to a network? ...
jojo osinga's user avatar
1 vote
2 answers
108 views

Cisco 3750 - configure to mimic multi location scenario

Good morning. For starters, I am less than a noob with cisco products. I can access, so basic trunking for our nec phone systems, etc. I have a 3750 that I'd like to configure to mimic a multi ...
TERRY's user avatar
  • 11
1 vote
1 answer
1k views

Mixed stack IOS upgrade - Cisco 3750x,3750G

I have a mixed switch stack : - Switch Ports Model SW Version SW Image ------ ----- ----- ---------- ---------- * 1 ...
Amin.K's user avatar
  • 61
3 votes
4 answers
1k views

Syslog severity level to 5 + ACL BLOCKED log

I am on a L3 switch C3750 IOS 12.2 and I want to log in the buffer (or just to the syslog server) all severity 5 messages and just the ACL Blocked level 6 messages. Is there a way to do this ? I've ...
Jey10's user avatar
  • 180
1 vote
1 answer
2k views

How to VLAN tag all traffic from one port before it goes out another

I am trying to figure out the configuration required to vlan tag with vlan 201 all traffic coming from one port and send it out another to the ONT for CenturyLink. I have a Cisco 3750e that I am using,...
Allen George's user avatar
2 votes
1 answer
9k views

vlan line protocol up/down

I have created L2 vlan & SVI's on core switch. but it shows status UP, Line protocol DOWN. Vlan11 x.x.x.x YES manual up down Vlan21 x.x.x.x ...
Suvi's user avatar
  • 61
4 votes
1 answer
2k views

Authentication error

I have set the username **** privilege 5 secret **** & applied aaa via console. now unable to access switch through console. After entering enable showing authentication error. can someone help ...
Suvi's user avatar
  • 61
0 votes
2 answers
161 views

3750 failed post. Internal fixed?

I have a 3750 manufactured in Feb of 2009, model number ws-3750-48ps-s V07. I'm consoled into it and when I power the switch, it boots (fans RPM) but no console display at all. The POE, stack, and ...
bstall10's user avatar
1 vote
3 answers
10k views

Cisco 3750 switch stack with different IOS images

There is a situation here, I am trying to add a new switch to an exisiting stack and i found out that the switch image in my current stack and the new switch is different. Can i still go ahead and add ...
user25763's user avatar
  • 111
2 votes
1 answer
4k views

Disable "ip redirect" Cisco 3750

I am experiencing high CPU utilization on a Cisco 3750. After consulting with Cisco TAC, it seemed we get a lot of icmp request that the switch redirects so asked what if I disabled the "ip redirect" ...
Fanttazio's user avatar
  • 125
1 vote
1 answer
442 views

AAA Authorization

I have a 3750x with TACACS AAA configured. If I login using TACACS, CLI commands run fine, no wait between commands. However, if I disconnect from network, taking away the ability to hit the tacacs ...
user23590's user avatar
6 votes
2 answers
3k views

Using channel-group mode on in my full Cisco enviroment

this is my first question over here. I have a question about using channel-group mode on or channel-group mode active. I have a core 3750x with 2 stacked SFPs nodes. Each pair of ports of a node ...
Felipe Oliveira's user avatar
2 votes
1 answer
793 views

Does "lacp port-priority" not work on Cisco Catalyst 3750 series?

I have a Cisco WS-C3750G-12S switch physically connected with ports Gi1/0/1 and Gi1/0/11 to Cisco WS-C3750G-24TS ports Gi1/0/1 and Gi1/0/27 respectively. Ports have different LACP port-priority: WS-...
Martin's user avatar
  • 1,121
3 votes
1 answer
301 views

Etherchannel trying to forward traffic through disabled ports

I am troubleshooting intermittent connectivity issues towards a WLC connected to a stack made of three 3750G switches. Part-number and software version of the switches are: Switch Ports Model ...
Daniel Yuste Aroca's user avatar
5 votes
2 answers
3k views

Cisco 3750-X Stack Bandwidth

I am currently managing a large datacenter spine-and-leaf topology. On our leafs, we use stacked 3750-X switches. I want to know how much bandwidth is currently going across the stack links (...
Aaron's user avatar
  • 51
3 votes
1 answer
214 views

Cisco Fiber switch perform at 100/1000

One of my switches is being replaced. It is a 24 port 100 base MTRJ Cisco switch. It is being replaced with a WS-C3750X-24S-E. Will this switch support 100/1000 or 1000 base only? I have some ...
phifer2088's user avatar
8 votes
2 answers
5k views

Impact of removing VTP from a production network

We are planning to remove VTP from a production network that has RPVST running. This is at the core (a pair of Cisco 3750s) and we are trying to weigh the impact it has on the production network. In ...
MFT's user avatar
  • 206
3 votes
5 answers
1k views

IPv6 address assigned to vlan interface of 3750 switch changes

When setting up my 3750 stacks, I enable IPv6 on the Vlan1 interface so that I can manage the stack over IPv6. The stacks are not doing any layer 3 routing. However, it seems that the IPv6 address ...
jcollie's user avatar
  • 131
6 votes
2 answers
4k views

SNMPv3 Setup - Cisco 3750

I am not a network guru by any means but need to setup our router/switch to use SNMPv3. I am installing What's Up Gold on our system and configured the settings (changed for this post) as follows: ...
JMeterX's user avatar
  • 163
3 votes
2 answers
8k views

portchannel cant bundle flow control mismatch

Having a strange issue here.. I replaced a stack member (2 members in a stack of Cisco 3750x). Both switches have a 10Gb card and I had a perfectly working LAG/etherchannel between to 10Gb ports. ...
user209's user avatar
  • 894
5 votes
1 answer
4k views

Setting up a switch to pass data from a SPAN port

Situation: We have a 3750 with a monitoring session setup on it, grabs a few VLAN's running over the switch and has a destination port on that device (normal SPAN not RSPAN). Historically speaking - ...
A L's user avatar
  • 3,310
4 votes
3 answers
5k views

Can you stack Cisco 3750 using ethernet cables?

I am just wondering if it's possible to stack Cisco 3750 switches using their ethernet interfaces? I don't have the proprietary stacking cables.
Muhammad's user avatar
6 votes
4 answers
397 views

Cisco SFP module: Determing Priority?

I have two 3750 Cisco switches that have two fiber cables/sfp modules hooked up on each. The second fiber is just for redundancy. I have installed two new 3750X switches on the rack for the upgrade, ...
Keven Culp's user avatar
25 votes
10 answers
339k views

How to find the port a device is connected to, based on IP, on a Cisco Catalyst switch

On a Cisco Catalyst switch, I need to find what port an end device is connected to. I have the IP address/host name. How do I quickly find the port?
Brett Lykins's user avatar
  • 8,308