Cisco Switching/Routing :: Catalyst 2960S - Dynamically Assign IP Address To Computers Via DHCP
Aug 30, 2012
I am administering a Catalyst 2960S switch and I would like to connect several computers to it. Some of those each have a static IP address. For a few of them, I would like the switch to dynamically assign an IP address to them via DHCP. Is the switch capable of doing this? If so, how can I do it? I tried looking through Cisco Network Assistant and I couldn't find it. Some web pages have suggested I telnet into the switch and issue commands like "ip dhcp ?" to see what commands are possible. I can telnet in and if I type but I get an "Unrecognized command" for both "ip ?" and "ip dhcp ?". This makes me think I'm reading the wrong web pages. I did come across the term "DHCP snooping". It seems relevant, but very difficult for me to grasp.
I just bought a Catalyst 2960S to test out the feature "Port-Based Address Allocation" which is required for our factory. I followed the instruction from Cisco IOS and did all the steps but I could not get it to work, my network client did not received the expected IP address that I configured.
Just I have upgraded some 2960S to IOS 15.0(2)SE from a IOS 15.0(1)SE3 and the catalyst don't switch any IPv6 traffic. Don't work any RA and also don't work any unicast IPv6 traffic from any interface. I can see some references to IPv6 changes in the FHS (First Hop Security) in the Release Notes, but no any reference to changes in the configuration.
The switches don't have any IPv6 specific configuration and the sdm is the default templata. Returning to 15.0(1)SE3 everything work ok.
On Catalyst 2960, and 3560E this IOS version seem to work fine with IPv6.
i want upgrade my catalyst 2960S and 3560x at midnight, but i am worried about config loss. If i upgrade my switch throught web interface, will need I reconfigure the switch?
we have Catalysts 2960S for switching in our Wireless high capacity backbone network. As agregation switch we are using 3560x.
I just need to know, if are these 2960S good solution for igmp snooping for whole IPTV stream. It put only a range from backbone and put out on another port. But just specified multicast addresses.
Imput will be 239.128.0.10 to 239.128.0.20 on Gi 0/1,Output wil be 239.128.0.10 - 15 on Gi 0/24
IPTV will be separated on different VLAN for eg VLAN 20,Is needed any priorization configured od switches?,The capacity for IPTV is around 500 mbps
I recently tried to manually format the flash on a model WS-2960S-48TS-L switch running IOS version 15.0(2)SE. While executing the operation I got the following error - mifs[8]: Failed to create superblock %Error formatting flash (I/O error).As a result the flash is no longer accessible by the switch. I spoke with Cisco and they indicated that a switch reload would remount the flash and make it accessable again but the .bin file would need to be reloaded using the xModem recovery procedure (what a pain).The next IOS version 15.0(2)SE1 will supposedly fix this bug but it has not been released yet. In the meantime if you are running 15.0(2)SE you may want to hold off performing a "format flash:" function on a 2960S.
We are using catalyst 2960S Lan Base IOS on Radio towers. We just bought 50 Accest points, thas are GPS synchronized. Problem is the APs need to be connected on L2-mac betwen each other. But at this time we are using port isolation on each switch (tower) by protected port function to isolate clients from each other.
My question is, is possible to specifi a Mac addresses in specific vlan thats can comunicate betwen protected ports? On tower is one Master unit and others are slave. I thing there is only 1 dirrection comunication - from master to slave.
specifying Cisco devices and I've made an error.I have 2 Catalyst 2960S switches (C2960S-24PS-L).Based on this snippet of web copy from the Cisco website:What's new for the Cisco Catalyst 2960-S Series Switches with LAN Base Software: # 10 and 1 Gigabit Ethernet uplink flexibility with Small Form-Factor Pluggable Plus (SFP+), providing business continuity and fast transition to 10 Gigabit Ethernet I bought a cable assembly "SFP-H10GB-CU3M" (3 meter copper twinax cable with 10GB SFPs on each end). Unfortunately, it appears after more careful reasearch that my specific model 2960S's are not directly compatible. , can I force these 10GB SFPs down to 1GB and get them to work with my switches or do I need to return and repurchase?
Multicast is not working between our two datacenter, we have catalyst 2960S (two stacked) as the internal lan switch, and catalyst 3560E as the external switch, same configuration for both datacenters.The two sites are connected using metro, the external switch (3560) is doing qinq and encapsulate the data from the internal switch with the metro vlan (611).
IGMP snooping is disabled for all switches, although we prefer to enable it for the internal switches.For each datacenter there is a different firewall which also act as the router, we are using fortigate as the firewall.Following is the important configuration section:
Port 43 in the internal switch is connected to the external switch (both sites):
Stumped again with my Catalyst 2950. Everything is working perfectly with wan/dhcp/router on fa 0/1 with all ports assigned to vlan1. All devices plugged in connect to the router correctly with ip's being assigned via dhcp.Instead of hooking up by console port I want to be able to SSH or telnet in to the switch using any port while still maintaining the above functionallity. Is it possible to assign a dhcp assigned ip address to vlan 2 and have vlan1 and 2 bridged? Or is there a better way of doing this ?
after upgrading about 35 Catalyst 2960 and Catalyst 2960S to IOS 15.0(2)SE2, we experience a memory leak on several switches. After some days / weeks the switches are not accessible via Console/Telnet/SSH/Web any more. Only SNMP seems to work properly.Attached users do not experience any decrease in service.
Trying to connect to the console, we get following error message:
"% Low on memory; try again later"
The only (temporary) solution is to reboot the switch. The behavior is similar to Bug CSCts52797.With regards to the Bug notes this bug should only affect Catalyst 2960 with 64MB of RAM and should already be solved with IOS 15.0(2)SE2.
Windows Server 2008 R2 has two DHCP scopes 192.168.1.x (for data) and 192.168.2.x (for VOIP). The Catalyst 2960-S has Vlan1 for the Data V LAN and V lan 2 for the VOIP network. How do I setup DHCP relay for Vlan2 to get their IPs from the scope on the Windows server?
Used to doing ip helper-address x.x.x.x in other Catalyst switches, but not available here.
I am trying to block all dhcp packets through 2960S lan base IOS. But when i set no trust interface for dhcp snooping, the dhcp packet source port will be err-disabled. Is there any other solution to block any DHCP packet through switch without interface or other service outage?Is possible to block DHCP packet through specific VLAN?
I know DHCP can assign more than just address, mask, and gateway. It can also assign a hostname, and DNS. Does anybody know if it can also be used to assign an SNMP address?
I would like to enable port security to hardcode the MAC address on the ethernet switch. There are 5 ethernet ports in the same ethernet switch to be assigned for one person (one note book), e.g. port 5, 6, 15, 16 and 23. The model of ethernet switch is cisco 2960S and one MAC address is configured on 2960S.
1. Does 2960S support this requirement to allow input the same MAC address to 5 different port?
2. If yes, can ethernet switch "smart" enough to forward the packages to "active" ethernet port which is connected to notebook and the rest of four ports are inactive.
3. if no, any solution or any work around to achieve this requirement
I have a cisco 878 router and I can’t assign ip address to it’s fast Ethernet interface. When I assign ip address give me this message: “you can not assign ip address to layer 2 interface”.
But I can not understand why give me this alert when I use a layer3 device?!
I have a RVS4000 router with DHCP enabled and in router mode.
The LAN is 192.168.2.x. The RVS4000 static IP address is 192.168.2.8
The router is not the RVS4000 and is at 192.168.2.1
The RVS4000 dhcp is assigning it's clients a default gateway of 192.168.2.8 instead of what I want 192.168.2.1. How can I get the RVS4000's DHCP server to assign another IP address other than its own as the default gateway to its DHCP clients?
DHCP enabled with default settings. Dynamic IP range from 192.168.0.100 - 192.168.0.199.Router shows laptop with 192.168.0.199 however when I check the IP on laptop I have 192.168.100.10 and both laptops are connected on my SSID with 90% signal strenght.
We have an ASA configured to access the internet, which works fine for clients who have an IP address assigned by DHCP, but not for clients with manually assigned IPs.
For instance, with the DHCP server configured to give IP addresses between 172.16.101.1 and 172.16.101.10, a device may get the IP address 172.16.101.1. This machine will have connectivity to the internet.
If we then configure DHCPd server range as 172.16.101.2 to 172.16.101.10 and statically assign the 172.16.101.1 IP to the client, it will not have internet access. It will, however have inside access and VPN access.
If I try to ping 8.8.8.8, the following is logged:
Where 'servers' is the name of the inside interface the request is made from and 'xxx.xxx.xxx.100' is the external IP. It seems as DNAT is not working when the client IP is static assigned.
How do i get the 12.4 code to assign a dhcp address to my ethernet interface from my server? I deleted the default config on the 1141 and searching has not turned up anything useful.
I've two Cisco 4500 running as core switches for huge and complex network. The two 4500 are going to act as dhcp server for several subnets. The easiest solution would be to split each DHCP pool in two, and assign the first half of the pool to one of the core switch and the second half of the pool to the second core switch. This would be a partial solution since if one of the two fails, the second core switch would not have enough dhcp leases available for all the devices connected for each subnet.For such a reason, I'm wondering if it the 4500 switches support a stateful redundant DHCP servers, so that the two switches can synchronize their DHCP lease tables. If this feature is available, I could define the same pools for both the switches without the risk of having duplicate ip addresses within the network.
I have customer who has as Core Switch one Cisco Catalyst 3750 with the IOS c3750-ipbase-mz.122-35.SE5.I know that this image support DHCP Server configuration, but I like to implementate new vlans (approx 15) and I want to know if this switch support 15 DHCP Servers.
I have a new catalyst 2960,and i want to enable DHCP SNOOPING,but,it doesn't work,the server is stilling offert addresses IP and it's not connected in a trusted port,the schema is very simple:1 switch catalyst 2960 PST-S,1 server dhcp and 1 pc client,the PC and the server are in VLAN 10,DHCP SNOOPING is enabled in all ports and no port is trusted,but the client get addresse IP after retyping ipconfig /release and ipconfig /renew in dos commande.the configuration and the version of the switch are in the file attached.I tested the same configuration in a catalyst C3560-24PS and DHCP SNOOPING work normally,i tested in other catalyst 2960-PST-S,but the same probléme:DHCP SNOOPING without effect,the commands typed is:
I'm attempting to configure a Catalyst 3560-X Switch to act as a DHCP Server. There is documentation that supports this feature. Below is my config procedure however after the completed procedue no IPs are handed out to clients. [code]
I Have a problem I'm trying to configure automatically my switch over ther DHCP when I start the switch it request an IP from the DHCP from here everythings is fine but it does nothing more,indeed I put on my dhcp the option 66 and 67 which is an adress of my TFTP server and a file to download and the switch seems not to understand theses options , I tried my dhcp with a cisco airport and everythings works fine the File from the TFTP is automatically downloaded into the airport...There is an option to add or am I missing something in order to make it work with my switch ?
I am going to creat VLANs very 1st time therefore for test purpose I have following simple scnerio.I have created 2 VLANs , VLAN2 and VLAN3 on Cisco Catalyst 2960 series switch. Ports 1-12 is assigned to VLAN2 and Ports 13-24 are assiged to VLAN3. Now I have configured DHCP on Microsoft Server 2003 defining 2 scopes with following configurations.
Scope 1 for VLAN 2--- Range is 172.16.0.17 to 172.16.0.30 with subnet mask=255.255.255.240 . Server IP address 172.16.0.17 ( Note: Address 172.16.0.17 is excluded from dhcp server Scope 1 and give to the MS server itself) Scope 2 for VLAN 3----Range is 172.16.0.33 to 172.16.0.46 with subnet mask=255.255.255.240 .
Now in Cisco 2960 series switches, under Vlan 2 and Vlan 3, I have following configurations...
interface Vlan2 ip address 172.16.0.30 255.255.255.240 ip helper-address 172.16.0.17 interface Vlan3 ip address 172.16.0.46 255.255.255.240 ip helper-address 172.16.0.17
Now the problem is when i connect a client computer to any port from 1-12, It gets correct IP address from Scope 1 but when I connect a computer to any port from 13-24, it does not get the ip address.
Further I want to do inter VLAN comunication as well for that purpose i Have an ISR 2900 series router. What further configuration i will have to do on router for inter vlan communication.
Do you have the ability to setup DHCP servers on this layer 3 switch? I know I can with my old 3550 switch. Want to upgrade and make sure this model supports setting up dhcp servers on it.
I have two 2960's in this new environment that I am administering. I am receiving a message on one unit (Designate it 2960-2) of %IP-4-DUPADDR: Duplicate address 192.168.168.8 on Vlan1, sourced by 3037.a63e.540. The "sourced by" address is the 2960-1. I do not know how these units were originally set up. How can I determine where the duplicate address is originating from.When I perform an ARP -a the address that corresponds to the 192.168.168.8 is the mac address of the ethersvi interface on the 2960-1. I
We want to filter IP traffic by MAC address on Catalyst 4500. Since we are using bonding (active-backup mode) we need those mac addresses appear on different ports. Below are solutions that we have tried: ACL but it does not work since mac acls only match non ip traffic (We CAN NOT use ip acl). Use a static mac address-table entry to ALLOW specific mac addresses. It does not work either since the same MAC address needs to be seen on a different port. Catalyst 4500 does not support auto-learn option (as e.g. Nexus 5000).
I disconnected and reconnected the powercable while holding on to the setup button until system, alert, setup go amber. The system led light began blinking green. I waited until one of the leds lights on the ports starts blinking green I then connected the ethernet cable connected to my pc. I made sure my lan connection on my computer was set to dhcp.In the docs claim it should take about 1 minute to grab a new ip address. After a few minutes i check the ipconfig on my pc and I get the apipa address.The setup light on the switch remains green while system is amber. The led for port 1 stopped blinking and remains green.My pc is not grabbing an ip address I don't know what else to do.
I have some Ethernet-connected cameras that all have the same Ethernet MAC address FF:FF:FF:0A:0A:0A. They were originally designed to directly connect to a Windows PC, but they can also connect through a simple unmanaged switch.A Catalyst 3560 switch won't forward packets to or from anything with that MAC address, at least not by default. Is there a way to convince the switch to do so?
It was my hope to replace the dedicated connections we have for these cameras with a separate VLAN for each camera, and switch them through our existing switch network. Given that all of the cameras use the same MAC address, putting them on the same network is out of the question, but different VLANs, where the only two devices on each VLAN were the camera and the PC that uses it, would be fine.
The switches run IOS 12.2(55) SE through SE3. I learned the camera MAC address from the PC's ARP table while the camera software runs; it turns out the cameras don't have a full IP stack either and don't even do ICMP.
