DHCP sometimes doesn't assign IP address
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Wireless access point maybe?
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@galt007
Do you have your "Old router" or a "Wifi Box" connected ?
Those are the usual suspects, when having a rouge dhcp server.You might not catch the offender by doing a pfSense packet trace, if the rouge unit is on the same L2 net as your devices getting a 192.168.2.x DHCP IP.
Well technically you should be able to see the broadcasts UDP 67/68.But i would make a "Mirror port" on your switch.
On the Netgear make a "Free port" a mirror of your "TV port", connect your linux Box to the mirror port , and "Fire up Wireshark as root".In wireshark select your Cabled interface that is connected to the mirror port, and start "sniffing".
To display filter wireshark to just show the captured DHCP packages, write : bootp - In the top line.
In theNow just sit back and wait for some dhcp packages to be shown.
Locate the ones that hands out a DHCP Offer contaning a 192.168.2.x" IP address to the TV. And note the MAC Address of the device sending.
Now to find the offender you have 2 choices (using the mac):
1: Use your switch to track down the mac , to a specific port.
2: Use a mac address lookup tool , to try to identify the vendor it was assigned to. Wireshark might already show the vendor in the packet trace.
Lookup url's:
https://www.wireshark.org/tools/oui-lookup.html
http://www.coffer.com/mac_find/Happy hunting
/Bingo
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@jarhead Geeting these on a packet capture of 192.168.2.0/24
ARP, Request who-has 192.168.2.1 tell 192.168.2.110, length 46
ARP, Request who-has 192.168.2.1 tell 192.168.2.110, length 46
IP 192.168.2.110.38973 > 192.168.2.255.15600: UDP, length 35
ARP, Request who-has 192.168.2.1 tell 192.168.2.110, length 46
ARP, Request who-has 192.168.2.1 tell 192.168.2.110, length 46the 110 address is the DHCP assinged TV address
AP's are setup in bridge mode without LAN ip addresses. WAN side of AP is DHCP but statically assigned by pfsense
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@bingo600 Thanks for the recipe. I did find a device 192.168.2.187 connected to my wifie network. Im going to reboot that AP and see if it connects again
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@galt007 said in DHCP sometimes doesn't assign IP address:
ARP, Request who-has 192.168.2.1 tell 192.168.2.110, length 46
You are probably looking for a device that uses : 192.168.2.1 as the ip address.
That ARP request above , smell a lot of a Client (192.168.2.110) , arp'ing for it's default gateway (192.168.2.1). Most often the default gateway ip is the same as the DHCP server ip on SOHO devices../Bingo
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@galt007
Well done.But from the manual : https://www.actiontec.com/wp-content/uploads/2017/02/ECB6000_UserManual.pdf
It doesn't seem like that device has a DHCP server built in. So i suppose the "Rouge Server" is at "The other end" of the Coax ...
What is it used for ??
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@bingo600 Had no idea what a rouge server was until the second time you posted it... rogue.
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@jarhead
Ah ... English isn't my native language (sorry) -
@bingo600 that's a good question. Think it came with my tivo which might explain why my tivo was trying to talk to 192.168.2.x.
Might have been how my tivo communicated with my tivo mini.
Main tivo works fine without it as it networked properly now.
