ip nat pool的问题

[thinkphp]

各位老师，本月公司升级了宽带，原来电信给的子网掩码是30位，现在升级后掩码是29位，现在IP地址比之前多了，我在路由器上配置了外网地址池，希望内网的客户端能从外网地址池里拿地址上网，但是配置好之后 show ip nat trans,地址转换的都是使用的地址池里第一个地址，后面的地址没有被翻译，请教各位老师指点，配置如下：
Router#sh run int gi0/0
Building configuration...

Current configuration : 201 bytes
!
interface GigabitEthernet0/0
description ***** To ISP *****
ip address 215.29.107.166 255.255.255.248
ip access-group AV in
ip nat outside
ip virtual-reassembly in
duplex auto
speed auto
end

Router#sh run int gi0/1
Building configuration...

Current configuration : 176 bytes
!
interface GigabitEthernet0/1
description ***** To Switch *****
ip address 172.16.0.254 255.255.255.0
ip nat inside
ip virtual-reassembly in
duplex auto
speed auto
end

Router#sh run | se nat
ip nat outside
ip nat inside
ip nat pool Global 215.29.107.162 215.29.107.167 netmask 255.255.255.248
ip nat inside source list NAT pool Global overload
Router#sh ip access-list
Standard IP access list NAT
10 permit 172.16.0.0, wildcard bits 0.0.0.255 (88092 matches)