曾招维,某局点SR88 个别IPOE用户获取不到地址
组网及说明
SR88--核心交换机--接入交换机--PC
问题描述
个别IPOE用户获取不到地址，trace用户信息，提示静态会话存在，查看会话并没有, 但获取不到地址的终端改一下MAC就能成功上线了。
过程分析
debug发现终端发dhcp请求，设备分的地址是x.x.16.16，这个地址是设备上静态会话中的， DHCP分配给用户，且此用户上来的带的二层vlan是1153，不是静态会话中的1024。因此dhcp和静态会话都异常。
对应的DHCP debug信息：
*Jan 13 13:34:30:644 2023 XL-BRAS-SR8806-X DHCPS/7/PACKET: -MDC=1;
To 255.255.255.255 port 68, interface Route-Aggregation1.2703
Message type: REPLY (2)
Hardware type: 1, Hardware address length: 6
Hops: 0, Transaction ID: 1792292162
Seconds: 0, Broadcast flag: 1
Client IP address: 0.0.0.0 Your IP address: x.x.16.16
Server IP address: 0.0.0.0 Relay agent IP address: 0.0.0.0
Client hardware address: x-x-847f
Server host name: not configured
Boot file name: not configured
DHCP message type: DHCPACK (5)
对应的trace用户信息:
*Jan 13 13:39:35:187 2023 XL-BRAS-SR8806-X USER/7/USER_TRACEINFO:[objectID=1][slotID=25][IPOE][user info:
MAC address: x-x-847f
Access interface: Route-Aggregation1.2703
Service VLAN: 2703
Customer VLAN: 1153
User name: 84a9-3e0f-847f
Access mode: IPoE ]
[trace info:The static session already exists]
配置中存在静态会话：
ip subscriber session static ip x.x.16.16 vlan 2703 second-vlan 1024 domain xl_J3 keep-online
解决方法
恢复办法：设备上dhcp配置forbidden-ip禁止此地址被dhcp分配即可，已告知现场客户。
恢复办法：
dhcp server ip-pool xl_j3
forbidden-ip x.x.16.16
