今天在做HADOOP的时候，安装JDK 1.7需要libc-2.4以上的版本，本着试试的想法，
从其他机器上COPY了一个libc-2.5.so,然后对libc.so.6重新做了一个软连接，
这一搞导致系统基本不能用了，所有的命令都报:
relocation error: /lib/tls/libc.so.6: symbol _dl_tls_get_addr_soft, version GLIBC_PRIVATE not defined in file ld-linux.so.2 with link time reference.
破坏步骤比较简单：
[root@sxtest01 tls]# mv /tmp/libc-2.5.so .
[root@sxtest01 tls]# ls -ltr
total 3552
-rwxr-xr-x 1 root root 32012 Jan 31 2007 libthread_db-1.0.so
-rwxr-xr-x 1 root root 50672 Jan 31 2007 librt-2.3.4.so
-rwxr-xr-x 1 root root 107800 Jan 31 2007 libpthread-2.3.4.so
-rwxr-xr-x 1 root root 213772 Jan 31 2007 libm-2.3.4.so
-rwxr-xr-x 1 root root 1529008 Jan 31 2007 libc-2.3.4.so <--这个是老的
-rw-rw-r-- 1 root root 1598712 Apr 11 2008 libc-2.5.so <--这个是我新复制过来的
lrwxrwxrwx 1 root root 19 Jul 27 2008 libthread_db.so.1 -> libthread_db-1.0.so
lrwxrwxrwx 1 root root 14 Jul 27 2008 librt.so.1 -> librt-2.3.4.so
lrwxrwxrwx 1 root root 19 Jul 27 2008 libpthread.so.0 -> libpthread-2.3.4.so
lrwxrwxrwx 1 root root 13 Jul 27 2008 libm.so.6 -> libm-2.3.4.so
lrwxrwxrwx 1 root root 13 Jul 27 2008 libc.so.6 -> libc-2.3.4.so
drwxr-xr-x 3 root root 4096 Dec 22 2009 i686
drwxr-xr-x 2 root root 4096 Dec 22 2009 i586
drwxr-xr-x 2 root root 4096 Dec 22 2009 i486
[root@sxtest01 tls]# rm libc.so.6
rm: remove symbolic link `libc.so.6'? y
[root@sxtest01 tls]# ln -s libc-2.5.so libc.so.6 <--重新对 libc.so.6做了一个软连接
[root@sxtest01 tls]# ll
ls: relocation error: /lib/tls/libc.so.6: symbol _dl_tls_get_addr_soft, version GLIBC_PRIVATE not defined in file ld-linux.so.2 with link time reference
[root@sxtest01 tls]# ls -ltr
ls: relocation error: /lib/tls/libc.so.6: symbol _dl_tls_get_addr_soft, version GLIBC_PRIVATE not defined in file ld-linux.so.2 with link time reference
[root@sxtest01 tls]# ls -ltr
ls: relocation error: /lib/tls/libc.so.6: symbol _dl_tls_get_addr_soft, version GLIBC_PRIVATE not defined in file ld-linux.so.2 with link time reference
[root@sxtest01 tls]# ll
ls: relocation error: /lib/tls/libc.so.6: symbol _dl_tls_get_addr_soft, version GLIBC_PRIVATE not defined in file ld-linux.so.2 with link time reference
[root@sxtest01 tls]# rm libc.so.6
rm: relocation error: /lib/tls/libc.so.6: symbol _dl_tls_get_addr_soft, version GLIBC_PRIVATE not defined in file ld-linux.so.2 with link time reference
[root@sxtest01 tls]# mv libc.so.6 /tmp
mv: relocation error: /lib/tls/libc.so.6: symbol _dl_tls_get_addr_soft, version GLIBC_PRIVATE not defined in file ld-linux.so.2 with link time reference
这个时候最好不要重启OS，否则就麻烦了。
恢复步骤如下：
[root@sxtest01 tls]# export LD_PRELOAD=/lib/tls/libc-2.3.6.so
[root@sxtest01 tls]# ls -ltr
total 3552
-rwxr-xr-x 1 root root 32012 Jan 31 2007 libthread_db-1.0.so
-rwxr-xr-x 1 root root 50672 Jan 31 2007 librt-2.3.4.so
-rwxr-xr-x 1 root root 107800 Jan 31 2007 libpthread-2.3.4.so
-rwxr-xr-x 1 root root 213772 Jan 31 2007 libm-2.3.4.so
-rwxr-xr-x 1 root root 1529008 Jan 31 2007 libc-2.3.4.so
-rw-rw-r-- 1 root root 1598712 Apr 11 2008 libc-2.5.so
lrwxrwxrwx 1 root root 19 Jul 27 2008 libthread_db.so.1 -> libthread_db-1.0.so
lrwxrwxrwx 1 root root 14 Jul 27 2008 librt.so.1 -> librt-2.3.4.so
lrwxrwxrwx 1 root root 19 Jul 27 2008 libpthread.so.0 -> libpthread-2.3.4.so
lrwxrwxrwx 1 root root 13 Jul 27 2008 libm.so.6 -> libm-2.3.4.so
drwxr-xr-x 3 root root 4096 Dec 22 2009 i686
drwxr-xr-x 2 root root 4096 Dec 22 2009 i586
drwxr-xr-x 2 root root 4096 Dec 22 2009 i486
lrwxrwxrwx 1 root root 11 Apr 7 13:48 libc.so.6 -> libc-2.5.so
[root@sxtest01 tls]# rm libc.so.6
rm: remove symbolic link `libc.so.6'? y
[root@sxtest01 tls]# ln -s /lib/tls/libc-2.3.4.so /lib/tls/libc.so.6
终于搞好了，虚惊了一场。
