Iptable Issue? Cant see devices on newly setup Access Point. Can ping, but not arp

CrewXp · 05-27-2016, 06:48 PM

I setup a wireless access point on my server and for some reason, everything works but automatic discovery features. I can't see any other devices, upnp devives aren't discovered, and I think it's a simple iptable or route issue I'm missing.

Example: -Device A plugged in ethernet discovers 20 local devices -Device A plugged in wireless discovers itself and the wifi only -Device A plugged in wireless CAN connect to others if manually specified IP -Device A can see NO other UpNp/DLNA/Share/Etc hooked wireless, but can ethernet

I solved this a long time ago, but can't remember what I did.

sudo iptables --list

Code:

Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere
ACCEPT     all  --  anywhere             anywhere

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
route

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         192.168.100.1   0.0.0.0         UG    0      0        0 eth0
default         192.168.100.1   0.0.0.0         UG    202    0        0 eth0
192.168.100.0   *               255.255.255.0   U     202    0        0 eth0
192.168.189.0   *               255.255.255.0   U     303    0        0 wlan0

ifconfig -a

Code:

eth0      Link encap:Ethernet  HWaddr b8:27:eb:31:1e:4b
          inet addr:192.168.100.153  Bcast:192.168.100.255  Mask:255.255.255.0
          inet6 addr: fe80::fb1:56b0:c113:f046/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:281701 errors:0 dropped:0 overruns:0 frame:0
          TX packets:89770 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:75550664 (72.0 MiB)  TX bytes:19734709 (18.8 MiB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:2491 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2491 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1
          RX bytes:234335 (228.8 KiB)  TX bytes:234335 (228.8 KiB)

wlan0     Link encap:Ethernet  HWaddr b8:27:eb:64:4b:1e
          inet addr:192.168.189.1  Bcast:192.168.189.255  Mask:255.255.255.0
          inet6 addr: fe80::f855:75b1:b821:5f5/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:26313 errors:0 dropped:24582 overruns:0 frame:0
          TX packets:2436 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:4191579 (3.9 MiB)  TX bytes:966693 (944.0 KiB)

network/interfaces

Code:

# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback

#auto eth0 # managed by ifplugd
iface eth0 inet dhcp
#hwaddress ether 1a:64:b6:bf:36:37

#allow-hotplug wlan0
#auto wlan0
#iface wlan0 inet dhcp
#pre-up wpa_supplicant -B w -D wext -i wlan0 -c /opt/max2play/wpa_supplicant.co$
#post-down killall -q wpa_supplicant






#Accesspoint start
up iptables-restore < /etc/hostapd/iptables.ap
#Accesspoint end

hosts

Code:

127.0.0.1       localhost
::1             localhost ip6-localhost ip6-loopback
ff02::1         ip6-allnodes
ff02::2         ip6-allrouters

127.0.1.1       UnitThree
192.168.189.1     UnitThree

Ser Olmy · 05-28-2016, 03:56 PM

You have two different IP networks, and your server acts like a router. That's why "ping" works (the server routes the packets back and forth), while "arp" doesn't show any IP-to-MAC bindings (the wireless and cabled networks are two entirely different Layer 2 networks).

Autodiscovery features like UPnP works by means of broadcasts or link-local multicasts. That type of traffic always stays within the Layer 2 network in question, and does not (and should not) be forwarded by routers.

If you want your wireless infrastructure to act as an extension of your existing cabled network, you will have to create a bridge.