PPPOE users under MA5200G could come online, and access QQ, but they fail to open webpages, although VLAN users could.
1. From checkup, we could know that users have come online, and the client could ping through to both gateway and DNS, as well as the domain name of website, indicating both routes and DNS are all normal.
2. It could not ping to big packets of 1500-byte, and after test step by step, it could ping through packets less than 1000-byte, failing to ping through packets more than 1000-byte.
3. According to checkup for the information of online users, it is found that both uplink and downlink bandwidth of users are all 8Kbps; executing debug radius packet command finds the bandwidth that radius has allocated is [Class(25)]  , less than 8K. The minimum granularity of bandwidth of MA5200G is 8K, so the bandwidth of online users is 8K, and only packets less than 1000-byte could be pinged through, not those more than 1000-byte. Therefore, they could not open the web pages. After changing the setting of bandwidth on radius, users could open the web pages through dialing again.
4. VLAN users use local authentication and the default bandwidth template of 10Mbps in domain, so VLAN users could communicate.
1. DNS under address pool of PPPOE users is configured falsely, and the DNS the users have gotten cannot resolve the IP address of website.
2. MTU is problematic.
3. Bandwidth is too little.
The case is caused by the third reason.