Cisco Switching/Routing :: Configure Two 3845 Routers To Act As DHCP Server / Relay?
Feb 14, 2012
I am trying to configure two 3845 routers to act as dhcp server and dhcp relay. Clients are connected to the router that relays all dhcp requests to the vrf instance which is used to connect it to the router wich is running dhcp server.
Router1
ip vrf dhcp_dns
rd 8:1
int gi0/0
ip vrf forwarding dhcp_dns
ip address 192.168.200.5 255.255.255.248
[code]...
So far I can see dhcp requests coming from the R1 and dhcp server on R2 replies with the dhcp offer but PC is not getting any ip.
How to configure cisco 3560 to force the client only can get ip by dhcp-relay server ?
The company i am working in has 5 vlans which have been set an lay-3 switch(3560), uses the dhcp-relay server .(in svi configuration: ip helper-address X.X.X.X) well , that works ok~
Now , I got my problem: I need to force the client only can get ip by dhcp-relay server, that means if anyone set static IP manunally , he can't really access to anywhere (to provent anyone set static IP with malignancy )
I know if a h3c router , how to set this configuration n svi configuration : dhcp relay security address-check enable ) the how to configure on a cisco 3560 ?
I have some DHCP trouble since I subnetted my network with a 2921. My clinets are in 172.16.2.0/23 and DHCP servers are in 172.16.5.0/24.Sometimes, randomly I guess, I get NACK from my DHCP server, and if I look into DHCP logs I got something like this:
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?
Is there a way to configure a DHCP server for my internal subnet of 192.168.20.1 which is on a 3550 layer 3 switch from my 5505 ASA Firewall.My subnet of 10.1.1.0/30 is connecting my 5505 to 3550. All I'm trying to do is run a DHCP server down to my hosts. The only options on ASA 5505 is
dhcpd address 192.168.20.1 - 192.168.20.254 outside or inside, which conflicts with my subnet of 10.1.1.0 used to connect my internal subnet of 192.168.20.1 for the whole network.
When I used my router it did not need the (inside, outside) keywords and just an ip helper-address command. How do I configure my my firewall DHCP server to propagate the 192.168.20.0 network through my 10.1.1.0 connection.
I need to configure a Cisco 2960 switch as a DHCP server. The current IP address will be on a different seed than the DHCP addresses. i.e.
Switch IP = 10.1.2.3, GW = 10.1.2.1, Subnet = 255.255.255.0 DHCP addresses would be 192.168.1.1 - 200, GW=???? (10.1.2.3?) and subnet would be 255.255.255.0
I am trying to get an understanding of some behaviour I am seeing on my N7Ks regarding DHCP relay.I have two identically configured Vlans interfaces both configured with the same two dhcp relay servers in the same order. The only difference between the two vlans is that one is HSRP active on the A side switch and the other is active on B side switch. All clients in Vlan136 (active on B side) are getting DHCP leases from the first of the two dhcp relay servers configured while all clients on Vlan 137 (active on A side) are getting DHCP leases from the second of the two dhcp relay servers. I would expect that all clients on both vlans would get leases from the first relay server configured unless that device was unavailable.
Would like to impliment VLAN's on Cisco IOS Software, C3560 Software (C3560-IPSERVICES-M), Version 12.2(25)SEB4...But I need a DHCP Realy to my Windows Based DHCP Server. How do I enable DHCP Relay on the 3560?
I have a 2921 with 4 segments: [code] My DHCP server is 172.16.5.2 and I need to serve clients from 172.16.2.0/23 by MAC address and only to that segment.
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 have upgraded a C3750G-12S-E to c3750-ipserviceslmk9-tar.122-55.SE5This switch is a distribution layer switch for one of my remote sites. it contains an ip helper-address on the site vlan's SVI.DHCP relay is no longer functioning for client PCs. Static address assignment allows full network functionality. I enabled debug ip dhcp server packet. [code] Actually I am betting you upgraded your IOS from something before 12.2(50)SE to 12.2(50)SE or later. We added enhancement CSCso19800 which will validate DHCP options when we are a relay agent.
I faced with issue on ME3800. [code] With that configuration there is no problem with DHCP Relay packets.But if I add on interface #xconnect 82.199.1 19.1 77 encapsulation mpls it will stop forward DHCP relay packets immediately. All other traffic transfers without problem.
We have a SBS 2003 server with two NIC's, one for the internal LAN and the other connecting to the WAG160Nv2 that is hooked up to the internet.The internal LAN clients are all getting IP addresses from the DHCP server in the SBS Server (192.168.16.XXX). The DHCP server is sat at 192.168.16.2.The only thing connected to the LAN ports on the WAG160Nv2 is the Internet facing NIC from the server.What I want to do is to get the WAG160Nv2 to give IP addresses to Wireless connections going through the router, can I configure the DHCP relay option on the WAG160Nv2 to do this, I have looked at the DHCP relay option but it doesn't seem to work, my wireless connections are getting private 169.254.xxx.xxx addresses.Also is there anything I can do to make the wireless more Apple friendly, iPhones and iPads drop of the wireless frequently, that's why I trying a different approach.
When I try to add an IP address to a port-channel interface on a 3845 ISR I am getting an error that seems to imply that only L2 etherchanneling is possible. Am I missing something?Cisco IOS Software, 3800 Software (C3845-ADVIPSERVICESK9-M), Version 12.4(24)T8,
sfo-c3845-1#sho run int port-channel 1 Building configuration... Current configuration : 31 bytes ! interface Port-channel1 end
I have a Cisco 7200 acting as the DHCP relay agent on my network. From a security standpoint, I want to disable the bootp server, with 'no ip bootp server'. What bearing, if any, does 'no ip bootp server' have on DHCP activity?
My network is set up such that I have a Wireless Network in VLAN 1, which is the primary network that we use. The subnet is 10.5.1.x.
My goal is to set up a completely isolated Guest Wireless Network, however it would work best. What I am trying to do now is I created a seperate VLAN (VLAN 2, IP range 10.5.2.x) and turned on DHCP on the WRVS4400N. However, in the Guest Network, it is always picking up a 10.5.1.x IP which is handed out by the DHCP server (10.5.1.5, Win 2003) and still routing all of the traffic to/from our private network.
Here's What I have set:
Wireless>Security Settings>Guest Network (SSID 2) Wireless Isolation (between SSID w/o VLAN): EnabledWireless Isolation (within SSID): EnabledSetup>LAN>VLAN 1 Router IP 10.5.1.1, WLAN IP 10.5.1.3DHCP Relay for 10.5.1.5Setup>LAN>VLAN 2 Router IP 10.5.2.1DHCP Enabled for 10.5.2.x subnetDHCP Relay option is grayed out (not sure why)Setup>Advanced Routing Inter-VLAN Routing: Disabled Any way to solve this would be fine. I just do not want traffic routing through our internal network. Ideally, if I could get the Windows server to hand out 10.5.2.x addresses, that would be perfect, but I'm not sure how to configure it for such.
I have a 3845 router. Setup SSH Version 2generated rsa keys (1024)set login localtransport input ssh and telnet is enabled since I can't get ssh connection working When I connect using SSH, I get the following error. server refused authentication protocol.
I have a 3845 running 12.4.13a which I want to upgrade to 12.4.24.After upgrade one of the interface that is configured for frame relay doesn't work anymore.In fact is the "service-module t1 timeslots" commands that can not be executed and the router throws that error.I tested this behaviour on two 3845s and the result is the same.Is this a bug or is an workaround for it?
I have two Cisco RV220W routers and I would like to realy DHCP from the home office to the remote office accross the IPsec Tunnel. Is this possible and if so how?
I have already gone into the IPv4 LAN (Local Network) settings on the remote router and set the DHCP mode to "DHCP Relay" providing the internal ip address of the home office router as the remote DHCP server.
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 can't seem to find any info on how to configure 2 DHCP server pools on a C3750, to use with 2 user vlans. The purpose is that users in vlan 1 should get an IP address from DHCP server1, and users in vlan 2 should get an IP address from DHCP server2. Both DHCP servers are configured in a stack of C3750 switches, which acts a a L2 switch.
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 using DHCP/TFTP to autoconfigure a 3945 router. The router properly obtains an IP address and finds the correct TFTP server. The issue lies in the download of the configuration file from the TFTP server. The router downloads the file, gives the "Ok" message, and prompts you to press Return to get started. When I view the running-config, several commands are missing from the Serial 0/0/0 section (HWIC-2T). If I modify the config file on the TFTP server to use Serial 0/0/1 instead and repeat the process, the configuration file loads without any issues and Serial 0/0/1 has all of the commands.
I also tried moving syntax around in my config file, but the end result is still the same. If I use Serial0/0/0 - I don't get all of the commands. If I use Serial 0/0/1, I do.
I've a Cisco 1941W router which is DHCP server for data-VLANs and uses ip-helper for voice-VLANs. [code] I don't know why I can't have IP from wireless voice VLAN whereas it is OK and wired voice VLAN and conf is the same!
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 used to use a CentOS self-made server for intranet for my little office, but I bouth few days ago a Cisco 861 router to replace the linux box.
1. I have 2 public IP classes from my ISP. 1 class is limitted to 80mbit upload, the other to 30mbit upload. So I need some sort of DNAT to be able to know exactly which intranet computer uses big internet and which one limitted internet. 2. I need DHCP server and with static IP addresses (one computer must always have the same IP address, etc).. i have my needs for this. 3. Also I need external access to some servers inside (web, ftp, etc) [code]
So far so good, all looks simple and I can achieve this in 2 hours on a centos linux box (correct routes, ip forwarding enabled and few iptables rules for NAT/SNAT/DNAT).
But on this brand new Centos router well, i'm not even successful in pinging the outside world, nor the inside world I'm tired of reading the forums, the documentation..i want (at first) a simple scenario: vlan+dhcp, fa4 with 1 public ip address and ACCESS to the real world. I wasn't able to achieve not even that much. [code]
