10

Word to the wise, don't connect a second hand switch to your production network before you wipe and/or re-configure it. Doing so can cause you MAJOR headaches if your network happens to use VTP. Without getting into the gritty details, connecting it could wipe or modify the VTP database used on your network (holding list of VLANs}, and basically cause your ...


7

First you should probably know about tab completion and the '?' key for online help in IOS. If I'd inherited a new Catalyst, I'd... Google "Password Recovery Catalyst 2900" Connect a Light-Blue Cisco console cable to it. You can make your own, but you'll still need a USB to serial adapter, they're $15 to $20 or so. Follow the instructions to reset the ...


6

The combination of switchport access and switch port trunk allowedmakes theswitchport access` configuration a no-op, right? You cannot have a port in access mode and trunk mode unless I am mistaken. Can someone confirm this for me? Not exactly. Let me break down the configuration: interface Port-channel1 switchport access vlan 100 switchport ...


5

Example config: shipping-2960# show run | i ntp ntp server 207.182.243.123 ntp server 69.65.40.29 prefer ntp server 208.53.158.34 To check status: shipping-2960# show ntp status Clock is synchronized, stratum 3, reference is 207.182.243.123 nominal freq is 190.7348 Hz, actual freq is 190.7286 Hz, precision is 2**18 reference time is D75F39BB.6F04B482 (...


4

Reference: https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/configuration/guide/cli/CLIConfigurationGuide/AccessTrunk.html#18749 Emphasis mine: By default, a trunk port sends traffic to and receives traffic from all VLANs. All VLAN IDs are allowed on each trunk. However, you can remove VLANs from this inclusive list to prevent traffic ...


4

If the way i have done is not true LACP, how come it is working with the Fortinet (which is set for 802.3ad Aggregate)? Seems setting channel-protocol lacp on my ports makes no difference (is it LACP by default)? By using channel-group 1 mode active you have defined the etherchannel to use LACP unconditionally. Depending on platform you have additional ...


4

Connect to the switch using a Cisco console cable and the serial (or USB->serial converted) connection. From there, you will need to configure its interfaces and local connection info. Being a used-device, you never know what configuration was left on the equipment. DHCP is most-certainly disabled by default.


3

The big driver for the 6509-V-E is that it is a front to back air flow, rather than the side to side airflow of the 6509-E. This is a very important feature in some data centers to maintain proper cooling.


3

The reason i ask i saw other configs in forums is they did not include the native VLAN in the list of allowed VLANs, i saw in a couple of places and wanted to check if a typo. The one big reason to not include the native VLAN is the list of allowed VLANs is that a native VLAN is a security risk. The current best practice is to not include the native ...


2

You use the command line to enable port mirroring/SPAN, and a reboot is not required. The below example (from the linked document) will mirror the traffic on Gigabit Ethernet port 0/1 to Gigabit Ethernet port 0/2. Switch(config)# no monitor session 1 Switch(config)# monitor session 1 source interface gigabitethernet0/1 Switch(config)# monitor session 1 ...


2

switch>enable switch# config t Switch(config)#username gozulin privilege 15 password yourpassword Switch(config)end switch# wr Note#1: you don't need to enter 0 or 7 --- try that. Privilege 15 will give you all the privilege as for a root user. Note#2: It is always good to not overwrite the previous credential until you know for sure your new user ...


2

You could also power the switch up - but as Cheekaleak said, not connected to your network. Use only a network cable between your PC and the switch. Try one of the "normalo" ports first. If you are familiar with linux, you could use cpdr (http://cdpr.sourceforge.net/, packages in major distros available). It shows you the management-ip as it is given in the ...


2

If you absolutely must do this in only Windows, I'd see if you can get a decent command line ssh program installed. Google showed me one that looks like it'll do what you need it to. With this and cmd.exe (or a unix/linux box with ssh and bash), you should be able to write a little for loop into the command line and have it do all the commands. I have a ...


2

The answer is Yes and No. You can make the changes, BUT hosts and devices won't be able to communicate with each other until and unless the ports they're connected to are members of the same VLAN. So if hosts 1 and 2 are connected to ports 1 and 2 in VLAN 1 and you make port 1 a member of VLAN 2 then hosts 1 and 2 won't be able to communicate until you make ...


2

I'm not sure there is a way to log the "show" commands themselves into an archive. You can achieve beyond logging config mode changes using Accounting TACACS+ features (an example with the ASA firewall is shown below, but same concept applies to switches/routers): http://www.cisco.com/c/en/us/td/docs/security/asa/asa72/command/reference/cmd_ref/a1_72.html ...


2

Higher end networking equipment tends to be modular, and come with a chassis with a set of module slots. Typically the main board will take up a slot (or possibly 2 in a redundant configuration) and the rest are available to mix and match high density or higher speed copper and fibre modules. It's no use to anyone without the chassis and management card, ...


2

Yes there is a problem and you are one step away from making a loop, but its not because of keeping Po1 and interface connected to the router in the same VLAN. When you Stack two switches, They work as one even if they are part of VSS(Virtual Switching System). The brain of the two switches become one and all the switching decisions are made by one switch(...


2

Based on the comments, it seems that you had not created the VLAN in the VLAN database on the switch. Not creating VLANs with the global vlan command for a stand-alone switch is a common source of problems. Switches that use trunks usually have VTP enabled, and the VLAN database will be populated by VTP. With stand-alone switches, and switches in VTP ...


2

Working link is not sufficient for working MAC level. Consider different VLANs to be very similar to different cabling and a switch. So you need to have a proper (tagged) VLAN for both your computer and your switch port. But it's only an infinite (4096) number of possible VLANs. Then you need to convince your party to ask for your MAC address - so you need ...


1

If the way i have done is not true LACP, how come it is working with the Fortinet (which is set for 802.3ad Aggregate)? Seems setting channel-protocol lacp on my ports makes no difference (is it LACP by default)? What you have done is configured a trunk. A trunk deals with sending and receiving packets for particular Virtual Local Area Networks (VLANs)...


1

In addition to the useful answers already given about USB/serial and not connecting unknown devices: by default a Cisco switch does not have an IP address configured and does not use DHCP to obtain one. It can do so, but it has to be configured first.


1

Azure Active Directory supports various authentication APIs and protocols, but LDAP isn't amongst them. However, Azure AD Domain Services (currently in preview) will be able to help you here, because they allow you to treat the user database in Azure AD just like an actual AD domain, including joining machines to it and performing LDAP queries. Some other ...


1

It depends on the software features of the Switch what options are available. http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-2960-s-series-switches/data_sheet_c78-726680.html Software Features Cisco Catalyst 2960-S Series Switches are available with the LAN Base and LAN Lite feature sets. LAN Lite models provide reduced ...


1

The 2960-S is a layer 2 switch. If you need routing between VLANs, you need a router.


1

Its a bit hard to follow what has happened based on your description - but try "show auto qos interface fastethernet 0/1" and see what it tells you You can find a good description of everything Auto QoS will configure and its expected behaviors @ http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_53_se/configuration/...


1

Access ports not in the VLAN that the unicast or broadcast originates from don't receive that traffic in the first place. That's the point of VLAN's. The excerpt from that article is making the point that instead of dealing with that traffic, if no access ports exist in the originating VLAN on a particular switch then VTP pruning "prunes" that traffic from ...


1

Turns out it was the bin file on the PC that was corrupted. I extracted it again from the tar archive and now it's uploading. Sigh. Always return to zero when you're stuck.


1

Unfortunately the new switches do not support these commands for shady SFP/SFP+'s. It has always been a unofficial command anyway. If the command is not there, the only thing you can do is to tweak the GBIC, but that's a whole different story.


1

I think you are not doing the copy xmodem: flash: command on the switch before trying to send the file. Also, make sure that you have a block with enough free space on the switch flash. You may need to do a squeeze if there is enough space, but not in a contiguous block. You need to understand that, at the very least, this will take many hours, and it may ...


1

You can't point to a default gateway that is outside of your local broadcast domain. i.e. if you have an IP address of 192.168.0.10/24 then your default gateway must be inside that network. That's the whole point of a default gateway. What I suspect you actually want to do is have some devices on your network use the default gateway on the 192.168.1.0/24 ...


Only top voted, non community-wiki answers of a minimum length are eligible