Difference Between A Switch And A Router Without DHCP?
May 17, 2012
Is there any difference between a switch and a router with DHCP turned off?I'm trying to connect a Mac and a PC (wired) to my Linksys E4200 but I don't have any ports left. I connected my Netgear WPN824 to my Linksys and turned DHCP off on the Netgear but I'm running into all sorts of problems:
- Mac/PC works for a few hours then looses network connectivity
- Mac/PC won't connect at all
- Mac will connect but I can't access my media server (PS3 Media Server) from my PS3 (which is wired directly to the Cisco)
I'm considering just giving up and buying a cheap network switch but was wondering if this will make any difference or will it just be a waste of money? With DHCP turned off, is the Netgear behaving exactly as a switch would anyway?
I have connected Huawei switch with Cisco switch using one single fiber with LX SFP. The port is up on one side (Blinking on Huawei side) and down on Cisco side..
I have a cisco 3560 24PS and its connected to two ADSL broard band routers.one is a personal broadband line using a Billion ADSL broadband router, and the other is a business broardband line using BT's 2wire broadband line.on the Billion routers i have various things attached like a NAS and a printers, both wired connections. then i have laptops and phones that connect over wifi, so its configured to act as a DHCP server
the only thing conncted to my 2wire router is my company's laptop (wired or wifi depending on where i'm working from), so again i have it working as a dhcp server.The switch is configured with multiple vlans, with dhcp scopes assigned for each vlan.I have a static route pointing all traffic to my Billion ADSL for internet connectivity.
The problem i'm having is that when i turn on the cisco switch, all wifi conected devices loose their conection. only 2 things get it working again, a reboot of the router, or disabling then enabling the DHCP service on the router.upon further analysis i was able to find out that the devices were not able to pick up an address from the router. again i looked deeper into this and i can see the following on logs of my router: [code]
so it seems that the router tuns off its DHCP capabilities because it detects that my Cisco switch is running DHCP services. I need to figure out how to keep the billion routers DHCP running when ever the switch is turned on.is there a way of filtering out any DHCP chat from the switch to the router?
We have a DHCP SERVER implemented in a cisco router 2610.This router is connected to a switch cisco 2960 configured as DHCP SNOOPING. At the switch appear the next log message: [code] The ip address: 10.100.200.1 belongs to DHCP SERVER configured at router cisco 2610. What to do so these log messages does not appear any more? Do I need to do some configuration changes at some switch or router?
when we use switch as dhcp server and we want to configure a DHCP relay on other subnet that is not connected to this switch, what is the DHCP server ip address for configuration of DHCP relay? Should we use vlan1 ip?
I am actually more of a 3Com guy than Cisco but I like to think I know my stuff and having just discovered this site I hope to join in as it looks a good place.I have a question about the general theroy underneath DHCP relay (IP Helper in the Cisco world I believe!)I've always put the DHCP server in VLAN1 only. A few weeks ago, I repatched the DHCP server in one of our offices (small site, single switch) into a different port by mistake. A few days ago I noticed (when doing something entirely unrelated) that I had left it in a port on both VLANs meant for PC's/phones. So, untagged on VLAN1, tagged on the voice VLAN. It had continued to work properly all that time however.By contrast, at a larger site, a new DHCP server came online and was put on a switch elsewhere in the building and was also put into a port on both VLANs - however things didn't work at all - of course we noticed immediately and changed the port setting to VLAN1 only, and it came back.In the second example, the server was on a different switch to where the main L3 switch for the Voice VLAN was (which also does the DHCP relay), and was connected over a fibre trunk link.Is there any reason why it should work on a single switch on a port on both VLANs, but not when connected over a trunk link? The server does not understand tagging. In the case where it worked, the phones were getting an IP from the correct scope; so the relay obviously must have been working with the server issuing an address based on the GIADDR field.
Have a client wanting to hand out public ip addresses to all clients from a PFSense Firewall terminating the internet connection.
How do I allow the Cisco Switches currently in place, configured with private ip addresses in the 10.10.x.x ranges and Vlans, where the main 3550 layer 3 has defined dhcp scopes for each vlan, to relay dhcp requests from all vlans to the PFSense firewall?
I assume I would take off the currently defined dhcp scopes for the vlans and configure each vlan/switch with the ip helper address and specify the PFSense firewall and that Nat would have to be disabled onthe firewall?
DHCP Relay on a SGE2000 switch.I have configured two VLANs on the switch, VLAN2 (192.168.10.x/24) and VLAN3 (192.168.9.x/24). I have the switch in Layer 3 mode. I have configured the DHCP relay server of 192.168.10.4 and the DHCP Interfaces as VLAN3. All of the IP Static Routes were generated by the switch.
If I put a client computer on a port that is Untagged VLAN 3 and try to get a DHCP address from the server on an Untagged VLAN 2 port I never get a response back.I have done some packet captures and here is what I have found:
I see the DHCP broadcast on the client computerI see the DHCP Request on the DHCP server coming from the IP assiged to the switch on VLAN 3 (192.168.9.254)I see the DHCP server respond with a DHCP OfferThe DHCP offer never gets to the client computer I can't seem to get a DHCP address to any system not on the same VLAN as the DHCP server. Option 82 is disable and I did try enabling it, which made no difference.
I currently have a the following configuration and am unable to get more than 2 DHCP addresses for the devices connected to the Cisco new SG 100-16 Switch.The AP have no trouble handing out DHCP to the wireless clients, but we are unable to get the SG 100-16 to be able to do the same thing to wired clients. It is currently connected to the 2960-8 in port 1. We can get 2 devices connected without a problem, but the 3rd machine and beyond do not work. Also, setting up a static IP does not work. Using a static will not even allow us to ping or tracer back to any devices beyond the SG 100-16.
I have sample lab dhcp-client ------- (vlan62) sg-300 switch (vlan62) ------ dhcp server
When I set on switch :
dhcp relay : enable option 82 : enable dhcp server address: ip of dhcp
When debug packets from client to server, there is no 82 option in dhcp discover packets. I mirror all traffic to mirror port with wireshark. I can see dhcp packets but without option 82.
I configured an DHCP server on cisco 3750 switch . Wher in w3750 gets connected to plain l2 switch 2960 on floor and machine gets connected to 2960 port. [code] Below is the description of problem:
-> The Cisco 3750 switch is the DHCP server. VLAN 108 is named as internet vlan.
-> Ports in Cisco 2960 switch has been configured with "switchport access vlan 108".
-> There were no problems at all and everything had been working smoothly.
-> 3 days back, users started complaining that they couldn't access the internet. Up on troubleshooting the issue, I found out that there was an issue with the DHCP server as the computer couldn't get any IP address at all. After setting static IP address, the internet started working again.
If I bind IP to MAc address reservation on core 3750 switch for some time of moment it works but after that machine gets unreachable .I restarted the 3750 switch and also all the 2960 switches over the weekend, however, the issue still hasn't been resolved yet. I did issue the command "clear ip dhcp conflict *", clear ip dhcp binding * but no joy at all.
After configuring DHCP, all the users needs to get IP from USER VLAN and all the servers should get IP from SERVER VLAN. If yes, what are the steps as I am very new in this kind of configuration.
I have made a topology by using one 3560 switch and 2 2950 switches. I have also made 2 vlans name Clients and other Servers and vlan 1 is for anagement purposes. The left 2950 switch is for clients and the right is for servers. Clients is vlan 2 and servers is vlan3 . Now what i want is that my dhcp is should assign ips to clients in vlans 2 provided that servers are in vlan 3. I am also using a border router and i have introduced a default route on the 3560 to the border router.
Now when i assign static ips to my clients pc and server dhcp then i can ping between vlans but when i try to assign ip through dhcp then it wont work. Also the default route on the switch to the border router doesnt seem to work. I can ping only the border router when i put a default route on the border router instead of the 3560 switch.
I have a 1250 AP connected to an Switch Cisco 3750. We have a SSID(v lan 1 - native) which get an IP Address from our DHCP Server(located in a Windows 2003 server). I added a new SSID in VLAN 2 and I would like no to use the DHCP Server but to make the AP get an IP Address from the pool I created in the own AP (ip dhcp pool Guest) but every time I try to connect the new v lan, it doesn't get an ip address.
Follow the settings of the AP.
version 12.4 no service pad service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption [Code]...
I have two WAP4410N plugged into my Catylist 3560 switches.One of these switches is my Default Gateway for the LAN.The only way I can get a device to connect to the WAP4410N is by assigning it a static IP. Then it works perfectly.
I am looking for a way to bind between a switch interface (cat 3750X) and a DHCP server reply.The switch can operate as the DHCP server .a PC connected to interface Gi 1/0/1 will lways get IP address 10.0.0.1 because it is connected to interface Gi 1/0/1, a PC connected to interface Gi 1/0/5 will lways get IP address 10.0.0.5 because it is connected to interface Gi 1/0/5 and so on... (no matter the source MAC address who sends the DHCP request).
I am having some issues with getting DHCP Relay to fuction properly over our SG300-20 Switch.Out current layout is as follows. Hanging off the SG300-20 are a pair of Clustered Checkpoint Gateways with VLAN'ed interfaces in Both of our 2 VLANs, a 3COM 4200G In VLAN1 which has the DHCP server (And all the other Servers) connected to it, and a Pair of HP Procurve 2520's Stacked in VLAN 2 to provide PoE for our Phones/connectivity for our PCs.The problem is I cannot get the DHCP Relay to fuction from VLAN 1 to VLAN 2. If I assign an address in VLAN 2 manually to a device connected to the Procurves, everything works fine. I am able to reach both VLAN 1 and VLAN 2, but DHCP aquisition fails even if the device is connected directly to a port assigned to VLAN 2 on the SG300. The SG300 is running at Layer 3 currently also.
Here is a copy of the running config: -------------------------------------------------------------------------------------------------------------- switch4db24f#show running-config vlan database vlan 2 exit interface range gi8,gi16 switchport default-vlan tagged
I am having 2960 switch and one port is configured with a VLAN and connected with an unmanageable switch and further one more unmanageable switch was connected to the primary unmanageable switch…
The topology will be 2960 switch -> unmanageable Switch -> unmanageable -> PC connected
The issue I am facing most of the PC are getting IP addresses through DHCP server and very few 5 or 6 PC’s out are not getting the IP from DHCP server.If I switch of the switch and switch on the issue is resolved for those and it will raise for some other PC’s.
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]
How to configure SF300 48port switch as DHCP Server or not.
My Configuration as below
I have 8 vlan configure in SF300 (SVI with ip address) isit possible to configure dhcp server and how i can apply access-list to restrict with other vlans.
