Arch Linux

Dave Cohen

Member

Registered: 2008-09-27

Posts: 126

ifconfig changes the essid I set with iwconfig

I'm in a cafe which has free wireless.  I also have a smart phone with me, with an ad-hoc wifi tether.  I want to use the ad-hoc wifi tether but my arch laptop keeps connecting to the cafe's wireless instead.  How can I force it to connect only to the essid I specify?

To start, I try to shut down any existing connections...

[root@archX60 ~]# ifconfig wlan0 down
[root@archX60 ~]# dhcpcd -x wlan0
dhcpcd: sending signal 15 to pid 3672
dhcpcd: waiting for pid 3672 to exit
[root@archX60 ~]#

Next, I tell it what I want used....

[root@archX60 ~]# iwconfig wlan0 mode ad-hoc
[root@archX60 ~]# iwconfig wlan0 essid Boomer
[root@archX60 ~]#

Where Boomer is my phone's essid.  And things look good so far...

[root@archX60 ~]# iwconfig wlan0
wlan0     IEEE 802.11abg  ESSID:"Boomer"  
          Mode:Ad-Hoc  Frequency:2.412 GHz  Cell: Not-Associated   
          Tx-Power=15 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off

Next, I've tried calling `ifconfig wlan0 up` and I've tried `dhcpcd -d wlan0' without calling ifconfig first.  In either case, the computer connects to the cafe's wifi instead of my phone....

[root@archX60 ~]# ifconfig wlan0 up
[root@archX60 ~]# 
[root@archX60 ~]# iwconfig wlan0
wlan0     IEEE 802.11abg  ESSID:"CAFELAVIE"  
          Mode:Managed  Frequency:2.412 GHz  Access Point: 00:1D:7E:10:29:29   
          Bit Rate=54 Mb/s   Tx-Power=15 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=53/70  Signal level=-57 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

Note the essid has changed to CAFELAVIE!  How can I insist on connecting only to Boomer?  Why does `ifconfig wlan0 up` trigger dhcpcd to get an ip address???

Thanks for any help.