Peplink Balance 380, PPTP server no longer working


#1

[edit:] problem solved. We had exhausted our DHCP pool of our internal DHCP server.

We’ve noticed a new problem since version 6.x of the firmware. Our PPTP server will sometimes stop responding to client requests.

Usually, a hard reboot would “solve” the problem, but the last time the problem wasn’t “solved” by rebooting. No clients (MacOSX, Windows, or iOS) are able to make a connection. No events are shown in the Peplink log.

Enabling the debug log on my mac, I see the following:

Tue Dec 15 22:23:04 2015 : publish_entry SCDSet() failed: Success!
Tue Dec 15 22:23:04 2015 : publish_entry SCDSet() failed: Success!
Tue Dec 15 22:23:04 2015 : pptp_get_router_address
Tue Dec 15 22:23:04 2015 : pptp_get_router_address 192.168.1.1 from dict 1
Tue Dec 15 22:23:04 2015 : PPTP connecting to server 'mailx.charltonslaw.com' (112.120.80.132)...
Tue Dec 15 22:23:04 2015 : PPTP connection established.
Tue Dec 15 22:23:04 2015 : PPTP set port-mapping for en1, interface: 4, protocol: 0, privatePort: 0
Tue Dec 15 22:23:04 2015 : Using interface ppp0
Tue Dec 15 22:23:04 2015 : Connect: ppp0 <--> socket[34:17]
Tue Dec 15 22:23:07 2015 : MPPE 128-bit stateless compression enabled
Tue Dec 15 22:23:08 2015 : PPTP port-mapping for en1, interfaceIndex: 0, Protocol: None, Private Port: 0, Public Address: 0, Public Port: 0, TTL: 0.
Tue Dec 15 22:23:08 2015 : PPTP port-mapping for en1 inconsistent. is Connected: 1, Previous interface: 4, Current interface 0
Tue Dec 15 22:23:22 2015 : PPTP error when reading socket : EOF
Tue Dec 15 22:23:22 2015 : PPTP error when reading header : read -1, expected 12 bytes
Tue Dec 15 22:23:22 2015 : PPTP hangup
Tue Dec 15 22:23:22 2015 : MPPE disabled
Tue Dec 15 22:23:22 2015 : Connection terminated.
Tue Dec 15 22:23:22 2015 : PPTP clearing port-mapping for en1
Tue Dec 15 22:23:22 2015 : PPTP disconnecting...
Tue Dec 15 22:23:22 2015 : PPTP disconnected

From the log, it appears the PPTP server is not responding at all

After a hard reboot (pulling the power for 15 seconds), I see the following:


Wed Dec 16 11:51:47 2015 : publish_entry SCDSet() failed: Success!
Wed Dec 16 11:51:47 2015 : publish_entry SCDSet() failed: Success!
Wed Dec 16 11:51:47 2015 : pptp_get_router_address
Wed Dec 16 11:51:47 2015 : pptp_get_router_address 192.168.1.1 from dict 1
Wed Dec 16 11:51:47 2015 : PPTP connecting to server 'mailz.charltonslaw.com' (223.255.133.202)...
Wed Dec 16 11:51:47 2015 : PPTP connection established.
Wed Dec 16 11:51:47 2015 : PPTP set port-mapping for en1, interface: 4, protocol: 0, privatePort: 0
Wed Dec 16 11:51:47 2015 : using link 0
Wed Dec 16 11:51:47 2015 : Using interface ppp0
Wed Dec 16 11:51:47 2015 : Connect: ppp0 <--> socket[34:17]
Wed Dec 16 11:51:47 2015 : sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x5db0bedc> <pcomp> <accomp>]
Wed Dec 16 11:51:47 2015 : rcvd [LCP ConfReq id=0x1 <asyncmap 0x0> <auth chap MS-v2> <magic 0x62b9b495>]
Wed Dec 16 11:51:47 2015 : lcp_reqci: returning CONFACK.
Wed Dec 16 11:51:47 2015 : sent [LCP ConfAck id=0x1 <asyncmap 0x0> <auth chap MS-v2> <magic 0x62b9b495>]
Wed Dec 16 11:51:50 2015 : sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x5db0bedc> <pcomp> <accomp>]
Wed Dec 16 11:51:50 2015 : rcvd [LCP ConfReq id=0x1 <asyncmap 0x0> <auth chap MS-v2> <magic 0x62b9b495>]
Wed Dec 16 11:51:50 2015 : lcp_reqci: returning CONFACK.
Wed Dec 16 11:51:50 2015 : sent [LCP ConfAck id=0x1 <asyncmap 0x0> <auth chap MS-v2> <magic 0x62b9b495>]
Wed Dec 16 11:51:50 2015 : rcvd [LCP ConfRej id=0x1 <pcomp> <accomp>]
Wed Dec 16 11:51:50 2015 : sent [LCP ConfReq id=0x2 <asyncmap 0x0> <magic 0x5db0bedc>]
Wed Dec 16 11:51:50 2015 : rcvd [LCP ConfRej id=0x1 <pcomp> <accomp>]
Wed Dec 16 11:51:50 2015 : rcvd [LCP ConfAck id=0x2 <asyncmap 0x0> <magic 0x5db0bedc>]
Wed Dec 16 11:51:50 2015 : sent [LCP EchoReq id=0x0 magic=0x5db0bedc]
Wed Dec 16 11:51:50 2015 : rcvd [LCP EchoReq id=0x0 magic=0x62b9b495]
Wed Dec 16 11:51:50 2015 : sent [LCP EchoRep id=0x0 magic=0x5db0bedc]
Wed Dec 16 11:51:50 2015 : rcvd [CHAP Challenge id=0xd9 <98cddf6ebb4f41f3173120e2f831e300>, name = "pptpd"]
Wed Dec 16 11:51:50 2015 : sent [CHAP Response id=0xd9 <5ccd552f70ea05692bd5ef77c7f68f150000000000000000773ad5f34fd8d31df649e44d47bb36e9fbccd14d247ae80300>, name = "pdwalker"]
Wed Dec 16 11:51:50 2015 : rcvd [LCP EchoRep id=0x0 magic=0x62b9b495]
Wed Dec 16 11:51:50 2015 : rcvd [CHAP Success id=0xd9 "S=F071CBDDCEB2C774AC29514ACB3EA2BE3C192594 M=Access granted"]
Wed Dec 16 11:51:50 2015 : sent [CCP ConfReq id=0x1 <mppe +H -M +S +L -D -C>]
Wed Dec 16 11:51:50 2015 : rcvd [CCP ConfReq id=0x1 <mppe +H -M +S +L -D -C>]
Wed Dec 16 11:51:50 2015 : sent [CCP ConfNak id=0x1 <mppe +H -M +S -L -D -C>]
Wed Dec 16 11:51:50 2015 : rcvd [CCP ConfNak id=0x1 <mppe +H -M +S -L -D -C>]
Wed Dec 16 11:51:50 2015 : sent [CCP ConfReq id=0x2 <mppe +H -M +S -L -D -C>]
Wed Dec 16 11:51:50 2015 : rcvd [CCP ConfReq id=0x2 <mppe +H -M +S -L -D -C>]
Wed Dec 16 11:51:50 2015 : sent [CCP ConfAck id=0x2 <mppe +H -M +S -L -D -C>]
Wed Dec 16 11:51:50 2015 : rcvd [CCP ConfAck id=0x2 <mppe +H -M +S -L -D -C>]
Wed Dec 16 11:51:50 2015 : MPPE 128-bit stateless compression enabled
Wed Dec 16 11:51:50 2015 : sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]
Wed Dec 16 11:51:50 2015 : sent [IPV6CP ConfReq id=0x1 <addr fe80::426c:8fff:fe2a:baeb>]
Wed Dec 16 11:51:50 2015 : sent [ACSCP ConfReq id=0x1 <route vers 16777216> <domain vers 16777216>]
Wed Dec 16 11:51:50 2015 : PPTP port-mapping for en1, interfaceIndex: 0, Protocol: None, Private Port: 0, Public Address: 0, Public Port: 0, TTL: 0.
Wed Dec 16 11:51:50 2015 : PPTP port-mapping for en1 inconsistent. is Connected: 1, Previous interface: 4, Current interface 0
Wed Dec 16 11:51:53 2015 : sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]
Wed Dec 16 11:51:53 2015 : sent [IPV6CP ConfReq id=0x1 <addr fe80::426c:8fff:fe2a:baeb>]
Wed Dec 16 11:51:53 2015 : sent [ACSCP ConfReq id=0x1 <route vers 16777216> <domain vers 16777216>]
Wed Dec 16 11:51:56 2015 : Received protocol dictionaries
Wed Dec 16 11:51:56 2015 : sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]
Wed Dec 16 11:51:56 2015 : Received protocol dictionaries
Wed Dec 16 11:51:56 2015 : sent [IPV6CP ConfReq id=0x1 <addr fe80::426c:8fff:fe2a:baeb>]
Wed Dec 16 11:51:56 2015 : Received protocol dictionaries
Wed Dec 16 11:51:56 2015 : sent [ACSCP ConfReq id=0x1 <route vers 16777216> <domain vers 16777216>]
Wed Dec 16 11:51:59 2015 : sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]
Wed Dec 16 11:51:59 2015 : sent [IPV6CP ConfReq id=0x1 <addr fe80::426c:8fff:fe2a:baeb>]
Wed Dec 16 11:51:59 2015 : sent [ACSCP ConfReq id=0x1 <route vers 16777216> <domain vers 16777216>]
Wed Dec 16 11:52:02 2015 : sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]
Wed Dec 16 11:52:02 2015 : sent [IPV6CP ConfReq id=0x1 <addr fe80::426c:8fff:fe2a:baeb>]
Wed Dec 16 11:52:02 2015 : sent [ACSCP ConfReq id=0x1 <route vers 16777216> <domain vers 16777216>]
Wed Dec 16 11:52:04 2015 : PPTP error when reading socket : EOF
Wed Dec 16 11:52:04 2015 : PPTP error when reading header : read -1, expected 12 bytes
Wed Dec 16 11:52:04 2015 : PPTP hangup
Wed Dec 16 11:52:04 2015 : MPPE disabled
Wed Dec 16 11:52:04 2015 : sent [LCP TermReq id=0x3 "MPPE disabled"]
Wed Dec 16 11:52:04 2015 : Connection terminated.
Wed Dec 16 11:52:04 2015 : PPTP clearing port-mapping for en1
Wed Dec 16 11:52:04 2015 : PPTP disconnecting...
Wed Dec 16 11:52:04 2015 : PPTP disconnected

So I can see something happening, but eventually the PPTP server stops responding.

I have confirmed that the user accounts and passwords have not changed. I can confirm that no firewall rules are in place that block pptp.

Can anyone make any suggestions on how I can further diagnose or debug this issue? Should I reset the router and enter in the configuration entirely from scratch?

Any help or advice would be greatly appreciated.


#2

Hi,

  1. This problem happened to all PPTP users?

  2. All PPTP users were disconnected when problem occur?

Please help to open ticket for us to investigate if problem persist. Thank you.


#3

1/ yes.

2/ I cannot say. No pptp users were connected, as far as I am aware of, at the time the problem reoccurred. Certainly all new connections failed after this point.

I’ve created a support ticket (#758084) with more detailed information.


#4

Noted. We will follow up from this ticket.


#5

Problem solved.

It turns out that the internal DHCP server had exhausted its IP pool. As a result, the PPTP clients were unable to obtain a network address and disconnect.

I’d never run out of IP addresses before, so it never occurred to me to check for this. Unfortunately the error messages were not helpful.

After expanding the address pool, the peplink is back to performing flawlessly.

Thanks to the peplink team for finding my problem.