Troubleshooting Tips

Frequently asked questions and troubleshooting tips about Linux, BSD, UNIX and MS-Windows servers.

I recently added SSD to my home server and reloaded the operating system. However, when I try to access my dm-crypt based old disk, I am getting the following error:

Reading all physical volumes. This may take a while...
WARNING: Duplicate VG name server01: Existing bc7YA8-eEXt-1aA1-OHTr-zJkA-ucd0-DsbRTc (created here) takes precedence over RIKiar-w3MG-Gzh5-VFWq-bkRT-9IFc-ia8k87
WARNING: Duplicate VG name server01: Existing bc7YA8-eEXt-1aA1-OHTr-zJkA-ucd0-DsbRTc (created here) takes precedence over RIKiar-w3MG-Gzh5-VFWq-bkRT-9IFc-ia8k87
Found volume group "server01" using metadata type lvm2
Found volume group "server01" using metadata type lvm2

The problem is my volume group. I set to to server01 on both old and new hard disk. How can I rename old LVM2? How do I access my old hard disk?

{ 1 comment }

How do I match dot files under Unix / Linux using bash shell? Why .* considered as harmful when matching dot files under bash shell?

{ 4 comments }

I have the following message whenever I use the apt-get command under Debian or Ubuntu Linux:

The following packages were automatically installed and are no longer required:
libaccess-bridge-java libjs-mochikit python-cheetah libjs-excanvas
libaccess-bridge-java-jni sabnzbdplus-theme-smpl tzdata-java
ca-certificates-java
Use ‘apt-get autoremove’ to remove them.
0 upgraded, 0 newly installed, 0 to remove and 4 not upgraded.

How do I fix this issue? Is it safe to remove all unwanted packages?

{ 1 comment }

I run a BT client and few other server program on Linux. Sometime these programs get overloaded with too many connections and crashes. If I restart my apps, I see lots of old IPs in a TIME_WAIT state. How do I force and and close everything in a TIME_WAIT state under Linux operating systems?

{ 1 comment }

I‘m setting up server on an Amazon EC2 compute instance powered by Suse Enterprise Linux server. I am using the following command to login into the my EC2 compute from OS X/Ubuntu desktop:

ssh -i suse-ec2-server-jp.pem root@ec2-xx-yy-zzz-yyy.compute-1.amazonaws.com

I am getting the following error:
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: UNPROTECTED PRIVATE KEY FILE! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
Permissions 0440 for 'suse-ec2-server-jp.pem' are too open.
It is recommended that your private key files are NOT accessible by others.
This private key will be ignored.
bad permissions: ignore key: suse-ec2-server-jp.pem
Password:

How do I fix this problem and login using ssh command?

{ 0 comments }

I would like to use argparse module for Python 2.6 under Debian Linux. However, the code is not working. How do I install and use argparse Python module under Debian Linux 6.x for Python version 2.5 or 2.6?

{ 0 comments }

When I type find . -type d -name "foo" command I get Permission denied error messages. How do I exclude all “permission denied: messages from the find command under Linux or Unix like operating systems?

{ 0 comments }