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 From:  Michael Iedema <iedemam at pluto dot dsu dot edu>
 To:  m0n0wall at lists dot m0n0 dot ch
 Subject:  mysterious pptp vpn behavior
 Date:  Wed, 30 Jun 2004 11:12:12 -0500
Greetings list,
I realize that the PPTP vpn has been the source of some confusion in 
past releases.  I personally have never experienced any packet loss 
while utilizing the service but today I've stumbled upon something new 
(I think). After looking through the mail archives I've only found one 
other person mention the same error.

The VPN at my work place has been in place for ~6 months with nearly no 
trouble.  Today, however, was a different story.

I received a phone call saying that a client could not connect and I 
checked out the system logs to find:

mpd: [pptpc0] error writing len 42 frame to bypass: Can't assign 
requested address
mpd: ENDPOINTDISC [802.1] 00 50 ba 54 93 7c
mpd: MP SHORTSEQ
mpd: MP MRRU 1600
mpd: AUTHPROTO CHAP MSOFTv2
mpd: MAGICNUM c42def48
mpd: MRU 1500
mpd: PROTOCOMP
mpd: ACFCOMP
mpd: [pptpc0] LCP: SendConfigReq #74
mpd: [pptpc0] error writing len 42 frame to bypass: Can't assign 
requested address
mpd: ENDPOINTDISC [802.1] 00 50 ba 54 93 7c
mpd: MP SHORTSEQ
mpd: MP MRRU 1600
mpd: AUTHPROTO CHAP MSOFTv2
mpd: MAGICNUM c42def48
mpd: MRU 1500
mpd: PROTOCOMP
mpd: ACFCOMP
mpd: [pptpc0] LCP: SendConfigReq #73


The post outlining the same error message is at:
http://m0n0.ch/wall/list/?action=show_msg&actionargs[]=50&actionargs[]=12

In it Adam Hirsch discovers that the culprit is the NAT implementation 
at his work place.  I would place the blame here as well except that 
this client is behind a m0n0wall and has had no problems connecting before.

Another proposed solution lists moving the PPTP client and server to a 
seperate subnet.  I've done this to ensure no rogue clients on the 
company lan are inhibiting the PPTP clients from obtaining an address.

I am running 1.1b15 and the connection worked last night from both Win2k 
clients and XP clients.  In the midst of troubleshooting this I went to 
my Boss's house to attempt to connect from both his XP & 2k machines. 
Both of his connections worked successfully and they are located behind 
a Linksys router.

As for the other clients in question, I have no information on what 
appliances they are situated behind, but my main concern is the m0n0wall 
based client failing to connect.

Has anyone run into this mysterious, seemingly unprovoked behavior?  If 
I've missed any important posts on the archive I apologize.  I limited 
my searching to my error message because that is what is the common 
factor in all of the troubles.

Thanks in advance for any help,
--Michael I.