我使用MINI2440和一个GPRS Modem进行GPRS拨号，遇到如下问题：ppp拨号成功后，ping一下DNS，成功了一个包后马上就被断开了，请各位帮忙看看是怎么回事？谢谢了！
操作记录如下：[root@FriendlyARM /]# pppd file /etc/ppp/peers/gprs &[root@FriendlyARM /]# timeout set to 15 secondsabort on (DELAYED)abort on (BUSY)abort on (ERROR)abort on (NO DIALTONE)abort on (NO CARRIER)timeout set to 60 secondssend (^MAT^M)expect (OK)^MOK -- got it
send (AT+CPAS^M)expect (OK)^M^M+CPAS: 0^M^MOK -- got it
send (AT+CSQ^M)expect (OK)^M^M+CSQ: 28,0^M^MOK -- got it
send (AT+COPS?^M)expect (OK)^M^M+COPS: 0,2,46000^M^MOK -- got it
send (AT+CREG?^M)expect (OK)^M^M+CREG: 0,5^M^MOK -- got it
send (ATS0=0^M)expect (OK)^M^MOK -- got it
send (ATE0V1^M)expect (OK)^M^MOK -- got it
send (AT+CGDCONT=1,"IP","CMNET"^M)expect (OK)^M^MOK -- got it
send (ATDT*99***1#^M)expect (CONNECT)^M^MCONNECT -- got it
send (^M)Serial connection established.using channel 1Using interface ppp0Connect: ppp0 <--> /dev/ttySAC1Warning - secret file /etc/ppp/pap-secrets has world and/or group accesssent [LCP ConfReq id=0x1 <mru 2000> <asyncmap 0x0> <magic 0xf965f258> <pcomp> <accomp>]rcvd [LCP ConfRej id=0x1 <magic 0xf965f258>]sent [LCP ConfReq id=0x2 <mru 2000> <asyncmap 0x0> <pcomp> <accomp>]rcvd [LCP ConfAck id=0x2 <mru 2000> <asyncmap 0x0> <pcomp> <accomp>]rcvd [LCP ConfReq id=0x1 <mru 1500> <asyncmap 0x0> <pcomp> <accomp> <auth pap>]sent [LCP ConfAck id=0x1 <mru 1500> <asyncmap 0x0> <pcomp> <accomp> <auth pap>]Warning - secret file /etc/ppp/pap-secrets has world and/or group accesssent [PAP AuthReq id=0x1 user="cmnet" password=<hidden>]rcvd [PAP AuthAck id=0x1 "Welcome!"]Remote message: Welcome!PAP authentication succeededsent [IPCP ConfReq id=0x1 <compress VJ 0f 01> <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]rcvd [IPCP ConfReq id=0x1 <addr 192.168.111.111>]sent [IPCP ConfAck id=0x1 <addr 192.168.111.111>]rcvd [IPCP ConfRej id=0x1 <compress VJ 0f 01>]sent [IPCP ConfReq id=0x2 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns3 0.0.0.0>]rcvd [IPCP ConfNak id=0x2 <addr 10.193.23.194> <ms-dns1 211.141.90.68> <ms-dns3 211.141.86.68>]sent [IPCP ConfReq id=0x3 <addr 10.193.23.194> <ms-dns1 211.141.90.68> <ms-dns3 211.141.86.68>]rcvd [IPCP ConfAck id=0x3 <addr 10.193.23.194> <ms-dns1 211.141.90.68> <ms-dns3 211.141.86.68>]Script /etc/ppp/ip-pre-up started (pid 716)Script /etc/ppp/ip-pre-up finished (pid 716), status = 0x0local IP address 10.193.23.194remote IP address 192.168.111.111primary DNS address 211.141.90.68secondary DNS address 211.141.86.68Script /etc/ppp/ip-up started (pid 718)Script /etc/ppp/ip-up finished (pid 718), status = 0x0
执行ping DNS命令后：
[root@FriendlyARM /]#
ping 211.141.90.68
PING 211.141.90.68 (211.141.90.68): 56 data bytes64 bytes from 211.141.90.68: seq=0 ttl=57 time=918.892 msrcvd [LCP TermReq id=0x2]
LCP terminated by peerConnect time 0.2 minutes.Sent 168 bytes, received 84 bytes.Script /etc/ppp/ip-down started (pid 724)sent [LCP TermAck id=0x2]Script /etc/ppp/ip-down finished (pid 724), status = 0x0ping: sendto: Network is unreachable
[root@FriendlyARM /]# Connection terminated.Modem hangup
