나같은 경우에는 사무실에서 리눅스 Masqurade 장비를 가지고 네트웍 통신을 한다.
따라서 Masqurade PPTP Pass through 기능을 활성화 시키기 위해 장비로 로긴해서 아래모듈을 올려준다.
[root@localhost ~]# modprobe ip_nat_pptp
[root@localhost ~]# modprobe ip_conntrack_pptp
아래 모듈이 활성화 되어있지 않으면 클라이언트에서는 619 오류가 발생되고 서버쪽에는 아래와 같은 메세지가 나타난다.
Apr 23 08:57:30 localhost pptpd[10934]: CTRL: Starting call (launching pppd, opening GRE)
Apr 23 08:57:30 localhost pppd[10935]: Plugin /usr/lib/pptpd/pptpd-logwtmp.so loaded.
Apr 23 08:57:30 localhost pppd[10935]: pptpd-logwtmp: $Version$
Apr 23 08:57:30 localhost pppd[10935]: pppd 2.4.4 started by root, uid 0
Apr 23 08:57:30 localhost pppd[10935]: Using interface ppp0
Apr 23 08:57:30 localhost pppd[10935]: Connect: ppp0 <--> /dev/pts/1
Apr 23 08:57:30 localhost pptpd[10934]: GRE: Bad checksum from pppd.
Apr 23 08:57:30 localhost pptpd[10934]: GRE: read(fd=7,buffer=80515e0,len=8260) from network failed: status = -1 error = Protocol not available
Apr 23 08:57:30 localhost pptpd[10934]: CTRL: GRE read or PTY write failed (gre,pty)=(7,6)
Apr 23 08:57:30 localhost pppd[10935]: Modem hangup
Apr 23 08:57:30 localhost pppd[10935]: Connection terminated.
Apr 23 08:57:30 localhost pppd[10935]: Exit.
Apr 23 08:57:30 localhost pptpd[10934]: CTRL: Client 218.xxx.xxx.xxx control connection finished
※ 정상접속시 메세지
Apr 23 10:04:31 node1 last message repeated 4 times
Apr 23 10:05:06 node1 pptpd[10713]: CTRL: Client 218.xxx.xxx.xxx control connection started
Apr 23 10:05:06 node1 pptpd[10713]: CTRL: Starting call (launching pppd, opening GRE)
Apr 23 10:05:07 node1 pppd[10714]: Plugin /usr/lib/pptpd/pptpd-logwtmp.so loaded.
Apr 23 10:05:07 node1 pppd[10714]: pptpd-logwtmp: $Version$
Apr 23 10:05:07 node1 pppd[10714]: pppd 2.4.4 started by root, uid 0
Apr 23 10:05:07 node1 pppd[10714]: Using interface ppp0
Apr 23 10:05:07 node1 pppd[10714]: Connect: ppp0 <--> /dev/pts/1
Apr 23 10:05:07 node1 pptpd[10713]: GRE: Bad checksum from pppd.
Apr 23 10:05:08 node1 pptpd[10713]: CTRL: Ignored a SET LINK INFO packet with real ACCMs!
Apr 23 10:05:08 node1 pppd[10714]: Cannot determine ethernet address for proxy ARP
Apr 23 10:05:08 node1 pppd[10714]: local IP address 10.0.0.1
Apr 23 10:05:08 node1 pppd[10714]: remote IP address 10.0.0.2
Apr 23 10:05:08 node1 pppd[10714]: pptpd-logwtmp.so ip-up ppp0 smileserv 218.xxx.xxx.xxx
기타 오류메세지 증상