dhcpcd doesn't remove alias address on interface-down?

[Paul Goyette <paul%vps1.whooppee.com@localhost>]

(Running amd64 7.99.19 with kernel and userland from sources that were 
updated on 2015-06-26 at 00:40:42 UTC)

I have a fairly simple network environment, with a single internet 
connection via a ISP-supplied WiFi/NAT router.  I have _nothing_ in my 
/etc/ifconfig.re0 file, and /etc/rc.conf has the following line

	dhcpcd=YES ; dhcpcd_flags="-C resolv.conf -L"

(The -C option is there because the ISP has [at least] one broken 
nameserver, so I hard-code resolv.conf to point to known good servers!)

Occassionally I need to reboot the router.  It seems that when I do, I 
end up with a new "alias" entry for the interface, but the previous 
alias is still there.  After a while, I seem to be accumulating aliases:

# ifconfig
re0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
...
       inet 192.168.1.10 netmask 0xffffff00 broadcast 192.168.1.255
       inet alias 192.168.1.9 netmask 0xffffff00 broadcast 192.168.1.255
       inet alias 192.168.1.7 netmask 0xffffff00 broadcast 192.168.1.255
       inet alias 192.168.1.6 netmask 0xffffff00 broadcast 192.168.1.255
       inet alias 192.168.1.3 netmask 0xffffff00 broadcast 192.168.1.255
...
#  arp -an
? (192.168.1.1) at 18:1e:78:97:11:ad on re0
? (192.168.1.3) at 30:b5:c2:05:0e:66 on re0 permanent
? (192.168.1.6) at 30:b5:c2:05:0e:66 on re0 permanent
? (192.168.1.7) at 30:b5:c2:05:0e:66 on re0 permanent
? (192.168.1.9) at 30:b5:c2:05:0e:66 on re0 permanent
? (192.168.1.10) at 30:b5:c2:05:0e:66 on re0 permanent
? (192.168.1.13) at a0:a8:cd:0d:e7:ec on re0
#

Since the reboot also causes other devices to re-acquire addresses, I'm 
having difficulty talking to anything that gets one of my earlier alias 
addresses.  :)


Is this expected/normal behavior?  If not, can it be corrected?  :)



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