unable to ping between my Fedora server and my laptop via wireless

dpmlq · 11-26-2008, 12:00 PM

My home setup: Fedora 9 server (connected via cable to DSL modem as IP address 1.2.3.4 over ETH1) and several WinXP boxes and laptops, all connected via CAT-5 using the 192.168.2.x subnet over ETH0.

I want to move my laptop (built-in wireless which works fine) upstairs, so I added a Linksys card to my server, configured it as an Ad-Hoc 192.168.3.1, added it to the firewall and masquerade, updated my routing tables . . . but I can't use it. Mechanically everything is fine and the laptop can see it and even connects, but nothing pings in either direction. Obviously I am doing something stupid; more accurately, I am _not_ doing something.

I must be missing a necessary step. I've read the FAQs and the HowTos but none of them explicitly describe what I'm trying to do. Do I need a separate router? Do my routing tables suck? Is using "Ad-Hoc" wrong for this scenario? (For now, I'm skipping both authentication and encryption --- I'll enable those when the basic connection is working.)

Thanks for your time. Pointers to appropriate docs appreciated.

ok
dpm

Code:

# lspci -v -s 3:0.0 
03:00.0 Network controller: RaLink RT2561/RT61 802.11g PCI
        Subsystem: Linksys WMP54G ver 4.1
        Flags: bus master, slow devsel, latency 64, IRQ 16
        Memory at fd9f8000 (32-bit, non-prefetchable) [size=32K]
        Capabilities: [40] Power Management version 2
        Kernel driver in use: rt61pci
        Kernel modules: rt61pci

# ifconfig wlan0
wlan0     Link encap:Ethernet  HWaddr 00:18:39:14:C6:3F
          inet addr:192.168.3.1  Bcast:192.168.3.255  Mask:255.255.255.0
          inet6 addr: fe80::218:39ff:fe14:c63f/64 Scope:Link
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:119 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:17763 (17.3 KiB)

# iwconfig wlan0
wlan0     IEEE 802.11  ESSID:"MYWLAN"   
          Mode:Ad-Hoc  Frequency:2.437 GHz  Cell: 9A:8A:39:E2:DB:EA
          Tx-Power=18 dBm
          Retry min limit:7   RTS thr:off   Fragment thr=2352 B
          Encryption key:off
          Link Quality:0  Signal level:0  Noise level:0
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.3.1     255.255.255.255 UGH   0      0        0 wlan0
0.0.0.0         192.168.2.1     255.255.255.255 UGH   0      0        0 eth0
192.168.3.0     0.0.0.0         255.255.255.0   U     0      0        0 wlan0
192.168.2.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
1.2.3.0         0.0.0.0         255.255.255.0   U     0      0        0 eth1
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr0
169.254.0.0     0.0.0.0         255.255.0.0     U     0      0        0 wlan0
0.0.0.0         1.2.3.1         0.0.0.0         UG    0      0        0 eth1

#

blackhole54 · 11-28-2008, 03:06 AM

Quote:

Originally Posted by dpmlq

Code:

# iwconfig wlan0
wlan0     IEEE 802.11  ESSID:"MYWLAN"   
          Mode:Ad-Hoc  Frequency:2.437 GHz  Cell: 9A:8A:39:E2:DB:EA
          Tx-Power=18 dBm
          Retry min limit:7   RTS thr:off   Fragment thr=2352 B
          Encryption key:off
          Link Quality:0  Signal level:0  Noise level:0
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

I'm not sure what your problem is and I have never done ad-hoc, but the higlighted line certainly looks wrong to me. Are you sure the two machines are really connected?

A wireless router would certainly be another option. I am using one just to connect wireless and wired machines together w/o even using the port that is designated for the Internet (or WAN). I also disabled DHCP so it simply functions as a switch with wireless capability.

c31c · 11-29-2008, 11:54 AM

I've got a very similiar setup and I think the same problem.
I want to use my Linux box as an AP for my notebook (a Macbook, running MacOSX 10.5).

Arch Linux, 3 Interfaces:
1 for the local wired net.
1 for dsl
1 for local wlan.

Code:

ifconfig wlan0
wlan0     Link encap:Ethernet  HWaddr 00:1D:0F:B5:29:C3  
          inet addr:192.168.3.1  Bcast:192.168.3.255  Mask:255.255.255.0
          inet6 addr: fe80::21d:fff:feb5:29c3/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:40 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:3816 (3.7 Kb)

Code:

iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:"macbook"  
          Mode:Ad-Hoc  Frequency:2.412 GHz  Cell: 2E:B6:78:36:D0:A8   
          Tx-Power=27 dBm   
          Retry min limit:7   RTS thr:off   Fragment thr=2352 B   
          Encryption key:off
          Power Management:off
          Link Quality:0  Signal level:0  Noise level:0
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

cat /sys/class/net/wlan0/carrier output is 1, which (as I've read elsewhere on the forum) should indicate that wlan0 is up and connected to a network (although: what does that mean for adhoc mode?)

I can see the network from my macbook, I can connect to it from the macbook. As soon as I have connected
i do from my linux box

Code:

iwlist wlan0 scan
wlan0     Scan completed :
          Cell 01 - Address: 2E:B6:78:36:D0:A8
                    ESSID:"macbook"
                    Mode:Ad-Hoc
                    Channel:1
                    Frequency:2.412 GHz (Channel 1)
                    Quality=56/100  Signal level:-53 dBm  Noise level=-89 dBm
                    Encryption key:off
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 6 Mb/s; 9 Mb/s
                              11 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s
                              48 Mb/s; 54 Mb/s
                    Extra:tsf=00000000ad6b5279
                    Extra: Last beacon: 10ms ago

dpmlq · 11-29-2008, 04:25 PM

Quote:

Originally Posted by c31c

I've got a very similiar setup and I think the same problem.

I notice that your device shows as RUNNING in the `ifconfig` output but mine does not. I wish I knew how meaningful that is.

ok
dpm

c31c · 12-01-2008, 09:10 AM

Yes, good catch! I don't know what 'RUNNING' signifies.

BUT: I got it working yesterday night.
First, it might have been a firewall issue (on the MacBook side).
Second, after deactivating the Mac firewall, I tested various Channels (Frequencies, right?) and (Transmit Rates).
I have an Atheros Chipset (AR2413), and it seems the new in-kernel driver ath5k doesn't have support for all features and all rates, yet.

I got good results with 24M, which is almost half of what this card should be able to do, but hey.

Some notes on Ad-Hoc:

man iwconfig says about the display of Signal level, Noise level: "In Ad-Hoc mode, this may be undefined and you should use iwspy."

Well, my Card doesn't support iwspy, or the driver doesn't, but maybe it will work for you.

Good luck
Cheers
c31c

blackhole54 · 12-02-2008, 02:28 AM

Thanks for the update and the report on what the man page says about my concern in post #2.

FYI, after reading dpmlq's post, I tried searching for information about RUNNING. Everything I could find lumped it together with UP. If anybody reading this knows the distinction between UP and RUNNING, I (and probably others) would sure like to hear it!