vpc里面的ecs安装vpn不成功

ifconfig始终无法看到ppp0，不清楚是不是阿里云ecs的内部问题。
配置完全没问题，在其他机房的服务器都能安装成功！

以下是配置情况。


service pptpd status                          
pptpd (pid  1205) is running...

[root@iZ94oy4jv7oZ ~]# cat /proc/sys/net/ipv4/ip_forward            
1

[root@iZ94oy4jv7oZ ~]# cat /etc/ppp/options.pptpd|grep ms-dns        
ms-dns 223.5.5.5
ms-dns 223.6.6.6

[root@iZ94oy4jv7oZ ~]# cat /etc/pptpd.conf|grep "localip 192.168.0.1"  
#localip 192.168.0.1
localip 192.168.0.1

[root@iZ94oy4jv7oZ ~]# cat /etc/pptpd.conf|grep "remoteip 192.168.0.234"
#remoteip 192.168.0.234-238,192.168.0.245
remoteip 192.168.0.234-238,192.168.0.245

[root@iZ94oy4jv7oZ ~]# tail /etc/ppp/chap-secrets                      
# Secrets for authentication using CHAP
# client        server  secret                  IP addresses
test pptpd 123456 *

[root@iZ94oy4jv7oZ ~]# service iptables status
Table: nat
Chain PREROUTING (policy ACCEPT)
num  target     prot opt source               destination        

Chain POSTROUTING (policy ACCEPT)
num  target     prot opt source               destination        
1    SNAT       all  --  192.168.0.0/24       0.0.0.0/0           to:120.25.XXX.XXX

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination  
2015-07-14 11:13:41