如何查看ubuntu版本信息？

couponweb@u1:~$ uname -a

Linux u1 2.6.31-14-server #48-Ubuntu SMP Fri Oct 16 15:07:34 UTC 2009 x86_64 GNU/Linux

couponweb@u1:~$ cat /etc/issue

Ubuntu 9.10 \n \l

couponweb@u1:~$ cat /proc/version

Linux version 2.6.31-14-server (buildd@crested) (gcc version 4.4.1 (Ubuntu 4.4.1-4ubuntu8) ) #48-Ubuntu SMP Fri Oct 16 15:07:34 UTC 2009

couponweb@u1:~$ lsb_release -a

No LSB modules are available.

Distributor ID: Ubuntu

Description: Ubuntu 9.10

Release: 9.10

Codename: karmic

couponweb@u1:~$ cat /etc/lsb-release

DISTRIB_ID=Ubuntu

DISTRIB_RELEASE=9.10

DISTRIB_CODENAME=karmic

DISTRIB_DESCRIPTION="Ubuntu 9.10"