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From: Greg Lehey <grog@lemis.com>
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Subject: Re: ifconfig: ioctl (SIOCAIFADDR): File exists
In-Reply-To: <199708040650.CAA02850@radford.i-plus.net> from Troy Settle at "Aug 4, 97 02:48:53 am"
To: rewt@i-Plus.net (Troy Settle)
Date: Tue, 5 Aug 1997 09:06:02 +0930 (CST)
Cc: questions@FreeBSD.ORG, ktsin@acm.org
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Troy Settle writes:
> From: Sin Key Teck <ktsin@acm.org>
>> Every time I add an alias to the fxp interface I would get the following
>> message:
>>
>> ifconfig: ioctl (SIOCAIFADDR): File exists
>>
>> What does it mean? How to get rid of it?
>
> How are you adding the alias?  what netmask are you using?  should be
> 0xffffffff ('255.255.255.255' if you can't read hex :)

Did you try this solution?  It doesn't work:

+ # ifconfig tun0 freebie 139.130.136.129 netmask 255.255.255.255 alias
+ ifconfig: ioctl (SIOCAIFADDR): File exists

In fact, it works anyway:

+ # ifconfig tun0
+ tun0: flags=8151<UP,POINTOPOINT,RUNNING,PROMISC,MULTICAST> mtu 1500
+         inet 139.130.136.133 --> 139.130.136.129 netmask 0xffffffff 
+         inet 192.109.197.137 --> 139.130.136.129 netmask 0xffffffff 

I think this is a bug.
Greg