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!
View 4 RepliesVersion 12.2(33)SXI
int vlan 1
description client vlan
ip vrf forwarding A
ip address 10.1.1.1 255.255.255.0
standby 129 ip 10.1.1.2
standby 129 timers 1 4
standby 129 priority 105
standby 129 preempt
ip helper-address 10.1.2.20
[code]....
dhcp requests are not making it to the dhcp server SAME VRF (ip helper-addres is not doing anything.....)extended vrf traceroutes on udp 67 sourced from vlan2 are fine
I am expecting udp unicast packets on port 67 "giaddr" relay packets on the DHCP server generated and sourced by the relay on Vlan1
eg. Mar 1 01:59:06.731: DHCPD: setting giaddr to 10.1.1.1
This exact setup works in our preprod environment with the same code.Only difference is we run Distributed etherchannel on the 6500's where this doesnt work.
Wireshark on the client I can see the requests being sent Going to check it with debug ip dhcp server to check the relay logs out of production hours.
I have seen so many people say it IS and ISN'T supported on this version of the code.e.g. [URL]
I am aware the helper-adddress should inherit the vrf of the interface ip helper-address vrf command is not supported.The fact it works in the PP environment.... could this be due to the Distributed EtherChanel difference? or just some bug....
My actual Scenario
1 x 4500 and 1 x 3560?They are gateways of 8 Vlans?They are doing HSRP in each of those Vlans?The 4500 is the Active?There is a DHCP Pool for each of those Vlans on both gateways using "ip dhcp excluded-address" I ensured that the range of provided ips by each DHCP server will not be overlapped Obs.: Reducing the lease time, I ended with the calls bringing related problems.
OK, every thing is blue, every thing is fine.But the network diagram is realy complex(41 switchs, 89 uplinks), and depending of how is the network flow, one or other server answer first or latter.
For many reasons I would like that the secondary DHCP server would answer only if the primary DHCP server goes down.To me, the bigger reason is that DHCP database would be only in one DHCP server.But there is other reasons.
I passed by many frustrated solutions:Try to force a delay on the answer on one of the servers. - Impossible.Try to disable DHCP server, and, using EEM, enable it only if router became active in HSRP. - I couldn't do It.
What I'm thinking now is use the HSRP resource to resolve it.On both routers I would put a "ip helper-address" pointing to an Virtual_HSRP_IP.And depending on which router is the active, him will answer the request.
My first doubt is:Would it work?The second doubt is:Could I use the same Virtual_HSRP_IP that exists on that Vlan(see example 1),or I would need to point it to a Virtual_HSRP_IP in a different Vlan(see example 2)?
Example 1
-----------------------------------
| 4500 |
-----------------------------------
interface Vlan1
ip address 10.10.0.2 255.255.0.0
ip helper-address 10.10.0.1
standby 1 ip 10.10.0.1
[code]....
Setting up a stand-alone WDS/PXE server.Current we have helper addresses setup to forward the DHCP requests from the different VLAN's to the DHCP server. The WDS/PXE server we are setting up is on its server. How do we craft the helper addresses so DHCP requests go to the proper server hosting DHCP and PXE requests go the WDS server?
Everything I seen on Microsoft Technet, lists using Helper Address as the recommended way, but assume both services are on the same server. Our helper address is as follows on each VLAN interface in router: ip helper-address X.X.X..This is a Cisco 3750.
Are any of the following commands supported on Nexus 5K switches when deployed with L3 card:
ip helper addressip forward-protocolip directed-broadcast
I'm interested to know whether we can configure ip helper in nexus 7000?
View 2 Replies View RelatedCisco PIX Security Appliance Software Version 8.0(2)
Device Manager Version 6.1(5)51
Cisco PIX Security Appliance Software Version 8.0(2)Device Manager Version 6.1(5)51 Running VPN on this device with an internal DHCP Pool tunnel-group JVusergroup type remote-accesstunnel-group JVusergroup general-attributesaddress-pool JVusergroup-DHCP-Pool I would like to use an external DHCP insted of the pix itselvf. How do I relay (IP-helper) DHCP request on the VPN policy to an external DHCP-server?
I would like to know if ip helper-address feature is working on a layer 2 switch (2950,2960) or you should use a Layer 3 switch to do that?
View 7 Replies View RelatedI own a 1941w that is covered by a service contract and I'm entitled to download software for it. But unfortunately I don't see any option to download AP software for it. I need an upgrade for the internal AP to connect it to a virtual WLC.Apparently I need ap801-rcvk9w8-tar.152-2.JB.tar to get this done.I can find it under the 800w series, but I don't own a service contract for that so I can't download anything.
View 1 Replies View RelatedI'm currently trying to get up to speed on a 1941W ISR. I belive i have most of the configuration correct based on reading the documents on this site. However, i'm noticing that my lan to lan network performance is very slow. Peaking out about 3mbs. I was reading some documentation that suggested MGF (MultiGigabit Fabric) might resolve this problem.
I have a basic setup in my test environment trying to emulate a branch deployment. 1941W connected to a access switch (3400).
- I'm getting slow perfomance (thoughput) between the vlans 66,30,10. Will MGF fix this problem? How do i configure it?
Building configuration...
Current configuration : 7474 bytes
!
! Last configuration change at 09:26:04 PCTime Fri Dec 28 2012 by xxx
! NVRAM config last updated at 09:26:05 PCTime Fri Dec 28 2012 by xxx
[Code]......
Is it possible to configure an 881 router to act as a DHCP server to 4 VLAN's each with a different scopes all through a single ethernet interface?
View 2 Replies View RelatedI 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.
View 3 Replies View RelatedI 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]
i'm interested if it's possible to set the NTP server via DHCP on an 2901 Router with 15.2(2) image.
i configured the interface gigabit 0/0 as dhcp client. The DHCP Server sends to me DNS, Default GW and NTP. All is working fine, but the NTP will not be configured. i tried to add an DHCP option request, but there is no NTP (42) value. [code]
is there any way to add the value NTP (42) for the DHCP request or isnt it possible?
I have trouble with a Cisco 892 Router from my Internet service provider.
Last week we switched from a virtual Router to a hardware Router. But after plugging it in our LAN Switch, the Windows DHCP Server stopped leasing IP's. I got many BAD_ADDRESS with MAC like e1:80:10:ac, e2:80:10:ac, e3:80:10:ac, e4:80:10:ac, e5:80:10:ac, ea:80:10:ac, eb:80:10:ac, ec:80:10:ac and so on.
I do not have access to the Router config, so I can not dump the config to you. We have a flat LAN, single SUB-Net(172.16.0.0/16) and no VLAN, no Spanning Tree. A Keep it Simple, Stupid(KISS) System.
A tech guy from service provider, is telling us, the error is not there fault and my switch is not correctly configured. But this is ********. For years we had a another Cisco Router from the precursor ISP and for 2 years the virtual Router from our current ISP. No trouble with my DHCP. But after plugging the new Router in, my DHCP stopped working.On the 892 is no running DHCP, but something interferences with my Windows Server 2008 R2 SP1 DHCP Server.
it's possible to let the Nexus 5548UP act as a DHCP server? (or if it will be possible in future releases)
View 3 Replies View Relatedtrying to configure a 1941W router... Spent many hours on these forums... The only thing I'm still stuck on is that, I'm not able to get an IP through DHCP on the BVI1 interface of the embedded AP.
Here is my router config:
Current configuration : 3490 bytes
!
! Last configuration change at 22:00:35 PCTime Tue Aug 21 2012 by root
[Code]......
I am running into a DHCP problem on a Cisco 891 running 15.0(1)M2. I am running DHCP on the router and want to reserve an address for a printer. I have done this hundreds of times on hundreds of routers. Per Cisco recommendation, I let the printer lease an address to see whether it uses it's "hardware-address" or "client-id". This printer uses the "hardware-address" format. The printer has leased 10.0.0.102 right off the bat. I want it at 10.0.0.50.
I have a DHCP pool, like this:
ip dhcp pool CLIENT
network 10.0.0.0 255.255.255.0
domain-name chsinc.ds
default-router 10.0.0.1
dns-server 10.0.0.1
lease 2
I create a "reservation" like so:
ip dhcp pool HP_LaserJet_Printer
host 10.0.0.50 255.255.255.0
hardware abcd.ef12.3456
Now I do a "show running-config" to see what I've put in and it looks just like above. Now we reset the network settings or change any network setting on the printer to force it to renew it's lease. What should happen and what usually happens is that the printer should request an IP, be offered 10.0.0.50, accept that IP and come up on that IP address. What is happening with this particular printer is that the printer requests a specific IP (the same IP that it had initially = 10.0.0.102), the router says OK and does not enforce the reservation. Then the router actually deletes the hardware-address config line right out of the running config. A "show running-config" shows that the reservation config now looks like this:
ip dhcp pool HP_LaserJet_Printer
host 10.0.0.50 255.255.255.0
See the logs below. Notice the ones in bold.
000226: Dec 12 17:34:01.382: DHCPD: Seeing if there is an internally specified pool class:
000227: Dec 12 17:34:01.382: DHCPD: htype 1 chaddr 101f.74b0.575c
000228: Dec 12 17:34:01.382: DHCPD: remote id 020a00000ae1e10100000001
000229: Dec 12 17:34:01.382: DHCPD: circuit id 00000000
[code]....
Is there a way to make the router enforce the reservation and not let clients just bring their own IP and actually make changes to the running-config of the router?
I seem to be having a problem with DNS name resolution after configuring my router (Cisco 3725 running IOS image: c3725-adventerprisek9-mz.124-25.bin) for handling DHCP requests.
Before I made the change, everything was working correctly; I could ping Google.com from a computer inside my LAN and would get response from one of Google's public IP's like normal.
I had a separate DHCP/DNS server running Windows Server 2008 handling the DHCP request and DNS queries.
When I made the change, I turned off the DHCP/DNS server and issued the following DHCP commands to my router:
Code...
I receive a question from a future customer about this future if its supported on " WS-C2960S-24PS-L":configuring 2 dhcp server on this swith ( 1 dhcp for voice vlan , and 1 for Data Vlan).I did some search , but i didnt find the answer .i have to advice a customer before ordering the switch.
View 2 Replies View RelatedOn a 4500 switch port , defined as access vlan 10, if the user connects his own dhcp server ( instead of the normal pc that should be connected ), will it cause issues with my existing network. the existing network is all static ip. In above case, will the dhcp server start looking out and assign dhcp ip's , if a user unknowingly removes his static ip and changes to obtain ip via dhcp option on the lan properties.
View 10 Replies View RelatedI'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]
View 1 Replies View RelatedCan I configure a DHCP Servero on the Nexus 7018?
View 2 Replies View RelatedI need to buy a cheap Cisco switch with DHCP server.Can you confirm that 2960-24-S, 2960-24TC-S and 2960-48TC-S be a DHCP server?
View 3 Replies View RelatedI have a DHCP server for a subnet that has only lightweight WAP's in it. The DHCP server is running on the gateway for this subnet which is a 3750X 2 switch stack running 12.2(53r)se2.I have the following configured:
ip dhcp excluded-address 10.1.10.161 10.1.10.162
ip dhcp pool DHCP-VL20
network 10.1.10.160 255.255.255.224
domain-name mydomain.net
dns-server 10.11.11.30 10.11.11.40
default-router 10.1.10.161
ease 3
The server hands out up to 18 IP addresses and no more, with 20 devices on the subnet. Scanning the subnet with a 3rd party network management system I see the following IP's never get handed out or used:
10.1.10.161 - 162 (manually excluded)
10.1.10.167 - 168
10.1.10.171 - 176
10.1.10.178
and of course 2 IP's I have manually excluded, 11 IP's in all that wont get handed out. It should only be 2 that don't get handed out. I've double and triple checked the exclusion and thats the only one. so I run a 'sh ip dhcp pool' and see this:
Pool DHCP-VL20 :
Utilization mark (high/low) : 100 / 0
Subnet size (first/next) : 0 / 0
Total addresses : 30
[code]....
[edit]I should also mention that "sh ip dhcp bind" does not show these randomly excluded IP's in use. They also do not show up in any arp table I can find.I have looked all over the config and I cant find where these extra 9 addresses are being excluded. how to free up these 9 seemingly random exclusions? Haven't issued a reload and I haven't deleted and rebuilt the DHCP server yet, production network.
I am wondering if it has its own DHCP router and if theres a command to enable it?Also Random side question. it hands out ip addresses to other devices (the 2950 im using infront of a router) but when I hook up another switch to this switch it doesnt initialize the port or try to connect? why.
View 1 Replies View RelatedOn a 4500 switch port , defined as access vlan 10, if the user connects his own dhcp server ( instead of the normal pc that should be connected ), will it cause issues with my existing network. the existing network is all static ip. In above case, will the dhcp server start looking out and assign dhcp ip's , if a user unknowingly removes his static ip and changes to obtain ip via dhcp option on the lan properties.
View 1 Replies View RelatedI just trying to setup a dhcp server in my catalyst 3560 switch for a nortel ip phones. I show you mmy configuration:
VOICE VLAN: 3
DATA VLAN: 1
S1:10.2.110.200
port:4100
Nortel IP Phones: IP 2002 (Firmware Version 0604D9H) & IP 1110 (Firmware Version 0623C7)
Switch Configuration:
aaa new-model!aaa session-id commonip subnet-zeroip routing!ip dhcp pool datos network 10.2.100.0 255.255.255.0 default-router 10.2.100.1 lease 0 2!ip dhcp pool voice network 10.2.110.0 255.255.255.0 default-router 10.2.110.200 option 191 ascii "VLAN-A:3" option 128 ascii "Nortel-i2004-A,10.2.100.200:4100,1,5." lease 0 2!!!!no file verify autospanning-tree mode pvstspanning-tree extend system-id!vlan internal allocation policy
[Code]...
This is the message that I am getting from my 1941w router. I have a isakmp tunnel built with a GRE tunnel going through it.
View 15 Replies View Relatedwe have approx. 70 Cisco 1941W routers deployed in our company. I used to be able to console into the internet wireless AP by issuing the below command:
service-module wlan-ap0 session
However lately this hasn't been working and AP just simply refuses connection. Here is what I have for Status. I have tried reseting the Service Module to no avail.
Router#service-module wlan-ap0 status
Service Module is Cisco wlan-ap0
Service Module supports session via TTY line 67
Service Module is failed
Service Module reset on error is disabled
Service Module heartbeat-reset is enabled
Service Module is in fail open
Service Module status is not available
a new LAN installation, two VSS pair 6509 core, 15 closets, with 3750 stacks. Floor 15 only, devices/hosts can ping teh DHCP server but cannot aquire IP addresses. no such problem on other floors?
portfast an dother parameters are intact.
With out using any server, will DHCP be configured in cisco 2950/2960 switch?I man cisco it self should work as a dhcp server also.
View 10 Replies View RelatedI have a 3911 router with a 1242 AP. The problem that I have is that when the user is trying to connect, the user get the OS Ip address 169.254.168.154 and I see that when I do the "show dot11 association" command, but when I do sh ip dhcp binding on the router I see
172.19.9.141 0100.18de.74db.14 Jan 31 2011 11:14 AM Automatic
The router is seeing as if the router gave the ip address to the user, but the reality the user was assigne the OS ip address 169. I did "debug ip dhcp server events" and I got the following:
Jan 31 11:09:06.752 EST: DHCPD: Seeing if there is an internally specified pool class:Jan 31 11:09:06.756 EST: DHCPD: htype 1 chaddr 0100.18de.74db.14
Jan 31 11:09:06.756 EST: DHCPD: remote id 020a00000a58218400000000Jan 31
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