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Topic: DHCP problem over WAN

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I am using openwrt trunk version on an alix 2d2 board. I am facing an problem where the the WAN ethernet port (eth0) is not able to receive an IP via DHCP from my home ISP. When I directly connected my home ISP's modem to my laptop's ethernet port, everything works fine my laptop is able to receive an IP via dhcp. My current network config on OpenWRT is

config interface loopback
        option ifname   lo
        option proto    static
        option ipaddr   127.0.0.1
        option netmask  255.0.0.0

config interface lan
        option ifname   eth1
        option type     bridge
        option proto    static
        option ipaddr   10.42.43.1
        option netmask  255.255.255.0

config interface wan
        option ifname   eth0
        option proto    dhcp

Does anyone have any idea about what may be going wrong? Any suggestions would be really helpful.

Thanks
Ashish

I tried the same router a friend's place with another ISP and it works fine there. My home ISP is Charter and I observed that it was not responding to any of the DHCP requests sent by udhcpc. Based on these observations, it seems that it may be problem with the ISP rather than Openwrt.

Thanks
Ashish

I can confirm the same problem with Charter, and the same testing method shows the same results.

Problem had been persistent since October of last year, although for the past several months it was corrected.  Then on Aug 13, my router's DHCP acquisition stopped working.  Check and unchecked the DOCSIS 3 checkbox, forged a completely different MAC address and watched the data flow; Charter never acks the request.

It does work with the stock Netgear firmware.

Rebooting the modem, the router gets 192.168.100.10 from the cable modem, and that address stays until the progression of querying the network for an address.

I filed a ticket with Charter, but nothing came of it.  Was going to open a ticket on the DSLReports Charter direct forum, but I'm leaving town for several weeks so I can't test.

I managed to make some headway on this issue, and it is a Charter issue.

If your router is deemed to make too many DHCP requests in a short period of time, the MAC address is banned and you can't get an address.  The banning seems to be extensive, greater than 48 hours.

Changing the MAC address and manually running udhcpc -t 2 -T 3 -A 300 works like a champ.  If I go back to the standard settings of -t 0 and unplug the cable modem a few times, eventually that MAC address will end up not working.  Fortunately, I've been using those of some old 3Com 10/100 cards.

I am unclear however, on the best method to getting these changes permanent.

After struggling with this for a while... EDIT: deleted content, I'm not just not sure of anything. Charter's DHCP server is extremely finicky. It can and will refuse to assign you an IP if too many requests are made (and it doesn't take many!). This may be due to the way IPs are assigned. Perhaps issuing too many requests causes their IPv4 address pool to dry up, as they may keep an IP active while idle for some period of time. It seems to resolve eventually. OpenWrt's default udhcpc configuration seems non-ideal for sure. The LuCI broadcast flag setting that mentions Charter does not seem to have an effect.

(Last edited by db90h on 6 Feb 2013, 05:41)

(theory updated)

Any headway? I believe the issue (from other searches) is that udhcpc does not send the broadcast flag, even when enabled to in OpenWRT configs. I have Charter and had no issues with my Cisco DPC3010 modem, but it died and I had to swap it today for a Motorola SURFboard SB6121 and OpenWRT would not pull a DHCP address.

As a quick workaround I added an old WRT54GL router I had sitting around with DD-WRT between my OpenWRT router and the modem and voila, the WRT54GL pulled an IP without issue and my LAN is back up.

This is the tcpdump showing that udhcpc did not send the broadcast flag despite that I have it enabled.

config 'interface' 'wan'
        option 'ifname' 'eth1'
        option '_orig_ifname' 'eth1'
        option '_orig_bridge' 'false'
        option 'proto' 'dhcp'
        option 'broadcast' '1'
13:24:19.750018 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 389)
    0.0.0.0.bootpc > 255.255.255.255.bootps: [udp sum ok] BOOTP/DHCP, Request from 30:46:9a:15:2f:90 (oui Unknown), length 361, xid 0x7b1c716b, Flags [none] (0x0000)
          Client-Ethernet-Address 30:46:9a:15:2f:90 (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Discover
            Client-ID Option 61, length 7: ether 30:46:9a:15:2f:90
            Vendor-Class Option 60, length 12: "udhcp 1.15.3"
            MSZ Option 57, length 2: 576
            Parameter-Request Option 55, length 8:
              Subnet-Mask, Default-Gateway, Domain-Name-Server, Hostname
              Domain-Name, RP, BR, NTP
            END Option 255, length 0
            PAD Option 0, length 0, occurs 80
13:24:21.656274 IP (tos 0x0, ttl 255, id 20870, offset 0, flags [none], proto UDP (17), length 341)
    10.164.240.1.bootps > 255.255.255.255.bootpc: [udp sum ok] BOOTP/DHCP, Reply, length 313, xid 0x3df8bac7, Flags [Broadcast] (0x8000)
          Your-IP 24.182.233.49
          Gateway-IP 24.182.224.1
          Client-Ethernet-Address 3c:75:4a:fb:14:6c (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Offer
            Server-ID Option 54, length 4: 68.114.37.12
            Lease-Time Option 51, length 4: 3600
            Subnet-Mask Option 1, length 4: 255.255.224.0
            RN Option 58, length 4: 1800
            RB Option 59, length 4: 3150
            Time-Zone Option 2, length 4: -21600
            Default-Gateway Option 3, length 4: 24.182.224.1
            Domain-Name-Server Option 6, length 12: 24.217.0.5,24.217.201.67,24.247.15.53
            LOG Option 7, length 4: localhost.
            TTL Option 23, length 1: 64
            MTU Option 26, length 2: 576
            END Option 255, length 0

My Gargoyle ps shows:

udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth0.2 -C

dhcp.script has:
# TODO: apply $broadcast

 udhcpc -t 0 -i eth1 -b -p /var/run/dhcp-eth1.pid -O b

Guessing the b opt is broadcast, though it doesn't appear to work.

Backfire r34427 w/ Busybox 1.15.3

Waiting on my toolchain to build for Attitude Adjustment.

Working correctly in Attitude Adjustment r35620 / BusyBox 1.19.4.

    0.0.0.0.bootpc > 255.255.255.255.bootps: [udp sum ok] BOOTP/DHCP, Request from 30:46:9a:15:2f:90 (oui Unknown), length 363, xid 0x198ea12, secs 3, Flags [Broadcast] (0x8000)
          Client-Ethernet-Address 30:46:9a:15:2f:90 (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Request
            Requested-IP Option 50, length 4: 24.182.246.199
            Server-ID Option 54, length 4: cnr01stlsmo.stls.mo.charter.com
            MSZ Option 57, length 2: 576
            Parameter-Request Option 55, length 7:
              Subnet-Mask, Default-Gateway, Domain-Name-Server, Hostname
              Domain-Name, BR, NTP
            Vendor-Class Option 60, length 12: "udhcp 1.19.4"
            END Option 255, length 0
            PAD Option 0, length 0, occurs 80
14:58:35.148409 IP (tos 0x0, ttl 255, id 11499, offset 0, flags [none], proto UDP (17), length 329)
    10.164.240.1.bootps > 255.255.255.255.bootpc: [udp sum ok] BOOTP/DHCP, Reply, length 301, xid 0x198ea12, Flags [Broadcast] (0x8000)
          Your-IP 24.182.246.199
          Gateway-IP 24-182-224-1.dhcp.stls.mo.charter.com
          Client-Ethernet-Address 30:46:9a:15:2f:90 (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: ACK
            Server-ID Option 54, length 4: cnr01stlsmo.stls.mo.charter.com
            Lease-Time Option 51, length 4: 3077
            Subnet-Mask Option 1, length 4: 255.255.224.0
            RN Option 58, length 4: 1538
            RB Option 59, length 4: 2692
            Default-Gateway Option 3, length 4: 24-182-224-1.dhcp.stls.mo.charter.com
            Domain-Name-Server Option 6, length 12: vip01olvemo.stls.mo.charter.com,vip01blvlil.blvl.il.charter.com,vip01aldlmi.aldl.mi.charter.com
            BR Option 28, length 4: 255.255.255.255
            END Option 255, length 0
            PAD Option 0, length 0
udhcpc -p /var/run/udhcpc-eth1.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth1 -C -B

5:24 PM 4/10/2015
Well... here we are a  year later .. same issue .. I added -b and changed hostname and mac .. still nothing ....wait ... as I type this I got an IP.. so its working now ... almost 4 hours later. I am not sure if it was adding the -b or changing hostname etc .. I also notice that the router gets a 10.  DHCP IP and then instantly gets  the real external IP .. it may have to do with that ...I still hope Charter dies in a fire smile my protip is to add the /lib/netifd/dhcp.script -f -t 0 -i eth0.2 -H Linksys -C -B -b

my current working  client reads ... lol ..

udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth0.2 --timeout=60 --tryagain=610 -b -H fuckyoucharter -C -B

5:24 PM 2/27/2014
So its  been months I found I have to plugin my cable modem first then the router and even sometimes I have to still change my mac address ... here some shit im working now... I added --timeout=60 --tryagain=610 to /lib/netifd/proto/dhcp.sh

udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth0.2 -H Linksys -C -B -b


https://forum.openwrt.org/viewtopic.php?id=38487

/lib/netifd/proto/dhcp.sh  ( is whre shit gets called if you want to hack it yourself ... )

/etc/config/network ( is where you add your optoins ... this is where your post to edit and add )






dhcpopts
http://www.linksysinfo.org/index.php?threads/cant-get-dhcp-working-on-wan.69442/

http://dev.man-online.org/man8/udhcpc/
-A,--tryagain N         Wait N seconds after failure (default 20)
 -t,--retries N          Send up to N discover packets
 -T,--timeout N          Pause between packets (default 3 seconds)

--retries=2 --timeout=5 --tryagain=310





cat /etc/config/network|grep dhcpo
        option dhcpopts ' --retries=2 --timeout=5 --tryagain=310 '


Ohh well did not fucking work ... on reboot:


so I hacked the /lib/netifd/proto/dhcp.sh script my fucking self ..

grep timeout /lib/netifd/proto/dhcp.sh   -A 5 -B 5

        proto_export "INTERFACE=$config"
        proto_run_command "$config" udhcpc \
                -p /var/run/udhcpc-$iface.pid \
                -s /lib/netifd/dhcp.script \
                -f -t 0 -i "$iface"  --timeout=60 --tryagain=610  \
                ${ipaddr:+-r $ipaddr} \
                ${hostname:+-H $hostname} \
                ${vendorid:+-V $vendorid} \
                $clientid $broadcast $dhcpopts




 ps w|grep udhcp
  628 root      1512 S    udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth0.2 -H Linksys -C -B
 1135 root      1496 S    grep udhcp



BTW FUCK YOU CHARTER ! FUCK YOU IN THE ASS ! my friend had to change his router too .. running STOCK firmware on different router.. so its fucking charter .. fuck you charter

rmccurdy.com OUT !

2:05 PM 11/24/2013
After powerloss no reconnect I had to unplug the cable modem for about 30min to reconnect.

UPDATE: 12:55 AM 11/16/2013
ARP floods are much better today... I can watch them go by with delay. Before its was so fast I could not even see them all. Holding steady with B1 so far ... wish me luck..I think it was just somebody on my node.

UPDATE: 9:41 AM 11/14/2013
Got dropped only once last night during usenet transfers. Dropped the threads down to 1 and set max speed to 300KB/s from 1000KB/s. I also found out that spam posts on a.b.movies ( just over 6million) on usenet caused my indexer to failsause and download for days straight so that may be the root issue .. I hope .. I ran out of disk space on it. Everything seems happy but I want openwrt back so I plan to wait a few days and push it to my WRT54G v2 or try the newer Asus RT-N13U B1. I am sure the B1 is faster than the 20year old WRT54G v2 ...

UPDATE: 10:49 AM 11/13/2013
Ok so its not firmware .. same random issues with dd-wrt after a few days ... so swapped out the router with a different one .. will see if it still has issues. Did notice my "weather direct" gateway was blinking a LOT so I unplugged it and internal traffic started to respond ... so maybe its this stupid weather gateway gone crap. The wifi internal worked but internet and wired devices did not. running ye ole WRT54G v2.2 with the weather gateway unplugged ... will see how that goes ...

UPDATE: 10:28 PM 11/8/2013
EDIT

UPDATE: 9:26 PM 11/8/2013
So far its working here is what I did ...
* unplugged the cable modem
* changed the mac address on the wlan
* set the broadcast flag to on
* apply / save
* stop the interface ( Under network )
* start the interface
Make sure it has the -B option in the console ( ps |grep udhcpc )
OLD: udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth0.2 -H Windowsrouter -C
NEW: udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth0.2 -H Windowsrouter -C -B
* stop the interface
* plugged in the cable modem and waited for it to go online
* clicked the start interface
* got an IP instantly...

Not sure if it was the -B or maybe they fixed something on the Charter side but so far so good ...  *Xs finger's*

* Charter
* the checking broadcast flag flag does not appear to do anything.
* I had filter put on my cable to block extended basic cable and after that its been wonky.. (with or without filter removed)
* I can plugin a windows laptop etc and get an IP address 'sometimes'
* Openwrt will get the 192.168.100.XXX IP and then blank and then never get the new DHCP IP that gets it online.
* I will try the udhcpc -p /var/run/udhcpc-eth1.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth1 -C -B but in my case I think its eth0.2
* The mac address is different for the wan port then the ASUS MAC on the bottom of the router. I dont have the Openwrt mac on hand but maybe is one blacklisted from Charter... but then again it worked fine for like week or two with this firmware.
* it appears maybe somebody is scanning because in a short time I get flood of ARP from one mac and it appears to be in sequential order  http://rmccurdy.com/scripts/downloaded/ … arp.pcapng I think 24.181.9.129 is doing the scanning and and  64:9e:f3:66:80:d9 is the gateway or something for that address even tho I was on a like 68.X.X.X address and nothing matched the ARP flood traffic I was getting.
* im running  http://rmccurdy.com/scripts/downloaded/OPENWRT/ AA_WORKING_EXTROOT_LUCI_openwrt-ramips-rt305x-rt-n13u-squashfs-sysupgrade.bin from https://forum.openwrt.org/viewtopic.php?id=40737
* I managed after a day to be online fine and then started pulling traffic for indexing usenet and maybe that or something else kicked me offline.

I think maybe a host one my node is doing scanning and making my whole termination system testy ... so when I push/pull traffic is drops me ...

I will update this post later after messing and testing different udhcpc flags ...

killall udhcpc
sleep 10
udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.script -f -t 0 -i eth0.2 -C -B

#Changing the MAC address and manually running udhcpc -t 2 -T 3 -A 300 works like a champ.

(Last edited by operat0r on 10 Apr 2015, 21:53)

hi, thanks for you postings.
i am luck to find your information, i have the same problem.
i am running openwrt CHAOS CALMER (Bleeding Edge, r44223) as x86 !!!!
an have a german cable-modem (cisco) es 3208 from provider unity-media.

i tried your findings without luck.

 5181 root      1060 S    udhcpc -p /var/run/udhcpc-eth1.pid -s /lib/netifd/dhcp.script -f -t 2 -i eth1 --timeout 20 --tryagain=300 -H Linksys -x 0x3d 3EB5B0BE8547 -B

as i run tcpdump -vv on my wan interface -i eth1 
i can see bootp packages from my router unanswered and some other on the segment are answered.
i a missing more knowledge to track down the problem, maybe someone can find here some hints?

i would be greatly thankful for any advise...
toz

08:04:14.584263 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 328)
    0.0.0.0.bootpc > 255.255.255.255.bootps: [udp sum ok] BOOTP/DHCP, Request from 3e:b5:b0:be:85:47 (oui Unknown), length 300, xid 0xba9fd36, secs 20, Flags [Broadcast] (0x8000)
          Client-Ethernet-Address 3e:b5:b0:be:85:47 (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Discover
            MSZ Option 57, length 2: 576
            Parameter-Request Option 55, length 7:
              Subnet-Mask, Default-Gateway, Domain-Name-Server, Hostname
              Domain-Name, BR, NTP
            Vendor-Class Option 60, length 12: "udhcp 1.22.1"
            Hostname Option 12, length 7: "Linksys"
            Client-ID Option 61, length 6: hardware-type 62, b5:b0:be:85:47
08:04:14.604114 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 10.45.61.92 tell 10.45.56.1, length 46



08:04:18.320453 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 328)
    10.207.4.1.bootps > 255.255.255.255.bootpc: [udp sum ok] BOOTP/DHCP, Reply, length 300, hops 1, xid 0xdfc1a643, Flags [Broadcast] (0x8000)
          Client-IP 95.222.129.68
          Your-IP 95.222.129.68
          Server-IP 81.210.129.74
          Gateway-IP 10.207.4.1
          Client-Ethernet-Address 5c:d9:98:e4:d0:8f (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: ACK
            Server-ID Option 54, length 4: 10.207.4.1
            Lease-Time Option 51, length 4: 3600
            Subnet-Mask Option 1, length 4: 255.255.252.0
            Default-Gateway Option 3, length 4: 95.222.128.1
            Domain-Name-Server Option 6, length 8: 80.69.100.102,80.69.100.230
08:04:18.341142 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 178.203.56.14 tell 178.203.56.1, length 46
08:04:18.351204 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 328)
    10.207.4.1.bootps > 255.255.255.255.bootpc: [udp sum ok] BOOTP/DHCP, Reply, length 300, hops 1, xid 0x975ad653, Flags [Broadcast] (0x8000)
          Client-IP 178.201.180.51
          Your-IP 178.201.180.51
          Server-IP 81.210.129.74
          Gateway-IP 10.207.4.1
          Client-Ethernet-Address 70:62:b8:6e:80:87 (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: ACK
            Server-ID Option 54, length 4: 10.207.4.1
            Lease-Time Option 51, length 4: 3600
            Subnet-Mask Option 1, length 4: 255.255.248.0
            Default-Gateway Option 3, length 4: 178.201.176.1
            Domain-Name-Server Option 6, length 8: 80.69.100.102,80.69.100.230
08:04:18.470418 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 10.45.50.181 tell 10.45.48.1, length 46

i searched a little bit, and i thing, i has to do with upstream proxy....
i get an ip from the cable-modem/router on startup, wich is 192.168.100.10....
than, after the cable-modem is fully booted and has intenet-uplink i can get no more ip from provider (upstream dhcp)..
this issues seems somehow adresses here: https://dev.openwrt.org/ticket/6819
(cable-modem blocks ip leases, because lan-clients pulled through switch-leak from wan-port...)
maybe this causes this?

how do i fix this? i will try later to shutdown all lan-adapter for connect to cable-modem. maybe this helps?..

(Last edited by toz.info on 21 Aug 2015, 12:12)

i saved my log from my tp-link, where it works.
my oberservation is, that my tp-link hardware-net-interfaces have all the same mac-adress. surprise.
i logged the discover, but i have now clue it this helps somehow..

i can recognize no Broadcast-Flag!!, and stages from:
DHCP-Message Option 53, length 1: Discover
DHCP-Message Option 53, length 1: Offer
DHCP-Message Option 53, length 1: Request
DHCP-Message Option 53, length 1: ACK


9:19:38.574811 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has ip-178-201-179-194.hsi08.unitymediagroup.de tell ip-178-201-176-1.hsi08.unitymediagroup.de, length 46
19:19:38.591660 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 328)
    0.0.0.0.bootpc > 255.255.255.255.bootps: [udp sum ok] BOOTP/DHCP, Request from f8:d1:11:be:34:2e (oui Unknown), length 300, xid 0x60579735, Flags [none] (0x0000)
      Client-Ethernet-Address f8:d1:11:be:34:2e (oui Unknown)
      Vendor-rfc1048 Extensions
        Magic Cookie 0x63825363
        DHCP-Message Option 53, length 1: Discover
        MSZ Option 57, length 2: 576
        Parameter-Request Option 55, length 7: 
          Subnet-Mask, Default-Gateway, Domain-Name-Server, Hostname
          Domain-Name, BR, NTP
        Vendor-Class Option 60, length 12: "udhcp 1.22.1"
19:19:38.593062 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has ip-95-222-130-51.hsi15.unitymediagroup.de tell ip-95-222-128-1.hsi15.unitymediagroup.de, length 46
19:19:38.630799 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 10.45.56.236 tell 10.45.56.1, length 46
19:19:38.738863 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 328)
    ip-178-203-204-1.hsi10.unitymediagroup.de.bootps > ip-178-203-207-51.hsi10.unitymediagroup.de.bootpc: [udp sum ok] BOOTP/DHCP, Reply, length 300, hops 1, xid 0x60579735, Flags [none] (0x0000)
      Your-IP ip-178-203-207-51.hsi10.unitymediagroup.de
      Server-IP 81.210.129.74
      Gateway-IP 10.207.4.1
      Client-Ethernet-Address f8:d1:11:be:34:2e (oui Unknown)
      Vendor-rfc1048 Extensions
        Magic Cookie 0x63825363
        DHCP-Message Option 53, length 1: Offer
        Server-ID Option 54, length 4: 10.207.4.1
        Lease-Time Option 51, length 4: 3470
        Subnet-Mask Option 1, length 4: 255.255.252.0
        Default-Gateway Option 3, length 4: ip-178-203-204-1.hsi10.unitymediagroup.de
        Domain-Name-Server Option 6, length 8: de-bom01a-dns-res-01.bom.unity-media.net,de-dtm01a-dns-res-01.dtm.unity-media.net
        BR Option 28, length 4: 255.255.255.255
        Hostname Option 12, length 12: "185933738bb9"
19:19:38.739624 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 328)
    0.0.0.0.bootpc > 255.255.255.255.bootps: [udp sum ok] BOOTP/DHCP, Request from f8:d1:11:be:34:2e (oui Unknown), length 300, xid 0x60579735, Flags [none] (0x0000)
      Client-Ethernet-Address f8:d1:11:be:34:2e (oui Unknown)
      Vendor-rfc1048 Extensions
        Magic Cookie 0x63825363
        DHCP-Message Option 53, length 1: Request
        Requested-IP Option 50, length 4: ip-178-203-207-51.hsi10.unitymediagroup.de
        Server-ID Option 54, length 4: 10.207.4.1
        MSZ Option 57, length 2: 576
        Parameter-Request Option 55, length 7: 
          Subnet-Mask, Default-Gateway, Domain-Name-Server, Hostname
          Domain-Name, BR, NTP
        Vendor-Class Option 60, length 12: "udhcp 1.22.1"
19:19:38.750139 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 328)
    ip-178-203-204-1.hsi10.unitymediagroup.de.bootps > ip-178-203-207-51.hsi10.unitymediagroup.de.bootpc: [udp sum ok] BOOTP/DHCP, Reply, length 300, hops 1, xid 0x60579735, Flags [none] (0x0000)
      Your-IP ip-178-203-207-51.hsi10.unitymediagroup.de
      Server-IP 81.210.129.74
      Gateway-IP 10.207.4.1
      Client-Ethernet-Address f8:d1:11:be:34:2e (oui Unknown)
      Vendor-rfc1048 Extensions
        Magic Cookie 0x63825363
        DHCP-Message Option 53, length 1: ACK
        Server-ID Option 54, length 4: 10.207.4.1
        Lease-Time Option 51, length 4: 3470
        Subnet-Mask Option 1, length 4: 255.255.252.0
        Default-Gateway Option 3, length 4: ip-178-203-204-1.hsi10.unitymediagroup.de
        Domain-Name-Server Option 6, length 8: de-bom01a-dns-res-01.bom.unity-media.net,de-dtm01a-dns-res-01.dtm.unity-media.net
        BR Option 28, length 4: 255.255.255.255
        Hostname Option 12, length 12: "185933738bb9"
19:19:38.796895 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 10.47.3.131 tell 10.47.0.1, length 46
19:19:39.109091 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has ip-88-153-148-7.hsi04.unitymediagroup.de t

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