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DHCP Problem
Posted: Fri Oct 23, 2009 9:33 pm
by piatthi
hi ALL , we have DHCP problem frequently, with dhcp server enable, some user does not get ip address from Mikrotik Box. same problem occur with DHCP relay, and sometime
when user get ip address, they are unable to be redirect by hotspot gateway.
we don't know what wrong ?
thanks for your help
Re: DHCP Problem
Posted: Sat Oct 24, 2009 12:01 am
by Chupaka
and what's in Log at that time?
Re: DHCP Problem
Posted: Sat Oct 24, 2009 3:54 pm
by Megateq
This is usually occurred when you have more than one dhcp server on network, try to check if there are any other Dhcp enabled on other devices like AP radios and try to disable them.
Re: DHCP Problem
Posted: Mon Oct 26, 2009 9:20 am
by greenfreq
I am having an issue where the dhcp-server on 4.1 is offering up an ip in reversed order... Below is the output from packet capture session. I've highlighted the offer in red. the scheme should be a pool from 10.10.20.2-10.10.20.254. When I look at the logs it shows that it offered up 254.20.10.10.
Any suggestions would be helpful.
No. Time Source Destination Protocol Info
2 0.003166 10.10.20.1 255.255.255.255 DHCP DHCP Offer - Transaction ID 0x4e025b0d
Frame 2 (342 bytes on wire, 342 bytes captured)
Ethernet II, Src: Routerbo_20:c0:cb (00:0c:42:20:c0:cb), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol, Src: 10.10.20.1 (10.10.20.1), Dst: 255.255.255.255 (255.255.255.255)
User Datagram Protocol, Src Port: bootps (67), Dst Port: bootpc (68)
Source port: bootps (67)
Destination port: bootpc (68)
Length: 308
Checksum: 0x9c77 [validation disabled]
Bootstrap Protocol
Message type: Boot Reply (2)
Hardware type: Ethernet
Hardware address length: 6
Hops: 0
Transaction ID: 0x4e025b0d
Seconds elapsed: 0
Bootp flags: 0x8000 (Broadcast)
Client IP address: 0.0.0.0 (0.0.0.0)
Your (client) IP address: 254.20.10.10 (254.20.10.10)
Next server IP address: 10.10.20.1 (10.10.20.1)
Relay agent IP address: 0.0.0.0 (0.0.0.0)
Client MAC address: Micro-St_d1:88:f5 (00:19:db:d1:88:f5)
Client hardware address padding: 00000000000000000000
Server host name not given
Boot file name not given
Magic cookie: (OK)
Option: (t=53,l=1) DHCP Message Type = DHCP Offer
Option: (t=54,l=4) DHCP Server Identifier = 10.10.20.1
Option: (t=51,l=4) IP Address Lease Time = 3 days
End Option
Padding
Re: DHCP Problem
Posted: Mon Oct 26, 2009 1:45 pm
by Chupaka
what hardware platform?
Re: DHCP Problem
Posted: Mon Oct 26, 2009 3:12 pm
by greenfreq
what hardware platform?
rb600a
Re: DHCP Problem
Posted: Mon Oct 26, 2009 3:49 pm
by Chupaka
hm... some flaw in big-endian architecture?.. please enable logging of dhcp, make supout.rif after lease offering and send to
support@mikrotik.com with detailed description
Re: DHCP Problem
Posted: Tue Oct 27, 2009 5:30 am
by greenfreq
hm... some flaw in big-endian architecture?.. please enable logging of dhcp, make supout.rif after lease offering and send to
support@mikrotik.com with detailed description
I did as you asked.. it should be noted that if you create the dhcp-server and the pool using the console >setup; script it does everything backwards... Its only if you do it through winbox that the server is created correctly.