[rhelv6-list] Different behavior of net.ipv4.ip_local_port_range between RHEL-5 and RHEL-6

[Santi Saez]

Hello,

Just found that net.ipv4.ip_local_port_range has different behavior 
between RHEL releases: until v6 although you have multiple source IPs 
you can only use a fixed number of local ports, seems that 
"ip_local_port_range" is a global configuration or limitation. On RHEL-6 
kernel (testing with 2.6.32-279) you can bind() to N local ports per 
source IP, it's a per-IP limit: total ports = ip_local_port_range x 
source IP.

The problem is that on RHEL-5 and 4 you can only make 
ip_local_port_range outgoing connections and you can't use different 
source IPs trick to increase this limitation. I have been testing and 
vanilla 2.6.32 kernel and other Linux distributions like Debian doesn't 
support this. What has been changed/patched on RHEL-6 to allow this? thanks!

Santi Saez