Thoughts About Collectd?

1 )How to change the run level from 6 to 3 or any run level in Centos 5.4 ?
2)I want to learn more about run level 4 (I know it is used to make changes in the boot time )?

respected to all
i am EMPkrishna. i am a new learner of red hat Linux, looking for a job in Linux system administrating, i have a good knowledge in Linux but i don't have any real time organization experience in Linux administrating. so please suggest me to learn the real time scenarios questions and answer @ troubleshooting questions in Linux asked in at the time of interview.
please suggest me the best way to get the knowledge on that tell me if any other sites like that to get real time questions and answer

This is a copy of my /etc/sysconfig/iptables.conf (w/o comments):
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 21 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 80 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 443 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT

- Added the port 80/21 entries.
vsftpd does work.

"iptables-save | grep 80" returns nothing.

My web server works (internal and external).

"systemctl is-active iptables" shows "inactive"
I have "just" gotten firewalld up and running thanks to questions answered here.

iptables is truly a mystery to me.

Can someone explain why my web server/vsftpd are up and working w/o iptables being active? How can I get my network and security both up and working safely together?

If I enable/activate iptables, is this going to break my web server?

Is this the appropriate forum for this question?

As always, thank you for your time and patience,

Skip

Hello,

My job is having me get back into Linux. It has been awhile since I messed with it. My company releases Software that runs on Linux. As such, when we release a new version of the software, we have it packaged with the entire Linux OS. As such, when it is sent to our clients, they install, and then have to reconfigure, the Host Name, IP Address, Netmask, and Gateway. Our test environment consists of over ten different Linux boxes and configurations. To make life easier for me, I have written a shell script allowing me a menu to change all of these and to also enable or disable the gateway and how to set/change the localadm password.

I want the script available to users to be able to run it anytime they need to. It works great. I would like to add one more thing to this. I want to be able to run the script automatically on the very first boot after the installation. The script is set up where you have to log in as root to run it. So here is the process I want to happen:

Install Disk
System starts up for very first time after install
Automatically logs in as root and runs script
Exits as root.

I realize Linux will only do what I tell it to. How do I tell it to do this?

I figured out there is a possibility that I can change the algorithm in the built-in cryptor, in the openSUSE install. The default algo loaded is AES and I want to change it to Twofish. I saw a post in gentoo's forums where it seems to be possible, although I don't know if I can do the graphic install after it nor how to procceed.

The command would be similar to:

Code:

cryptsetup -y --cipher twofish-cbc-essiv:sha512 --key-size 256 luksFormat /dev/sda3

What should I do? How to install the system afterwards? (with graphical install). Also, is there a way to check the encryption description after the system install?

I want to install openSUSE 12.3

Hi,

I am trying to understand the difference between char devices and block devices.
I understand the basic, which is that char devices input/output data one character at a time, whereas block device input/output data block by block. But for char device driver, most of the time we are able to read/write an array of data using the read/write system call. This "array of data" sounds like a block of data to me, except that it's not fixed in size as for block devices. With this thinking, can I say that I can effectively achieve block read/write with a char device driver?
And what are the other differences?

Thank you all,
Wei

Hey guys, I am a little confused about run level programs. (concerning centos)

I know when the system boots up the orders will be

bios
MBR
GRUB
kernel
init
runlevel

to my understanding - etc/init looks at /etc/inittab
then where is the run level located?
is it /etc/rc.d/rc0.d...
/etc/rc.d/rc1.d
/etc/rc.d/rc2.d
are these run level programs?

if so, what about /etc/init.d ? doesnt that also execute run level programs?

and how does it know what to start? where does it look

thanks guys just a bit confusing where what looks for what

I am trying to allow local users to us the ftp for my site (really, any user would work, I just thought this would be easiest). I am trying to make it so that I can upload themes, install plugins, etc on a WordPress site hosted on my Ubuntu 14.04 machine. Here is the contents of my vsftpd.conf file from /etc/

# Example config file /etc/vsftpd.conf
#
# The default compiled in settings are fairly paranoid. This sample file
# loosens things up a bit, to make the ftp daemon more usable.
# Please see vsftpd.conf.5 for all compiled in defaults.
#
# READ THIS: This example file is NOT an exhaustive list of vsftpd options.
# Please read the vsftpd.conf.5 manual page to get a full idea of vsftpd's
# capabilities.
#
#
# Run standalone? vsftpd can run either from an inetd or as a standalone
# daemon started from an initscript.
listen=YES
#
# Run standalone with IPv6?
# Like the listen parameter, except vsftpd will listen on an IPv6 socket
# instead of an IPv4 one. This parameter and the listen parameter are mutually
# exclusive.
#listen_ipv6=YES
#
# Allow anonymous FTP? (Disabled by default)
anonymous_enable=NO
#
# Uncomment this to allow local users to log in.
local_enable=YES
#
# Uncomment this to enable any form of FTP write command.
write_enable=YES
#
# Default umask for local users is 077. You may wish to change this to 022,
# if your users expect that (022 is used by most other ftpd's)
local_umask=022
#
# Uncomment this to allow the anonymous FTP user to upload files. This only
# has an effect if the above global write enable is activated. Also, you will
# obviously need to create a directory writable by the FTP user.
#anon_upload_enable=YES
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
#anon_mkdir_write_enable=YES
#
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
dirmessage_enable=YES
#
# If enabled, vsftpd will display directory listings with the time
# in your local time zone. The default is to display GMT. The
# times returned by the MDTM FTP command are also affected by this
# option.
use_localtime=YES
#
# Activate logging of uploads/downloads.
xferlog_enable=YES
#
# Make sure PORT transfer connections originate from port 20 (ftp-data).
connect_from_port_20=YES
#
# If you want, you can arrange for uploaded anonymous files to be owned by
# a different user. Note! Using "root" for uploaded files is not
# recommended!
#chown_uploads=YES
#chown_username=whoever
#
# You may override where the log file goes if you like. The default is shown
# below.
#xferlog_file=/var/log/vsftpd.log
#
# If you want, you can have your log file in standard ftpd xferlog format.
# Note that the default log file location is /var/log/xferlog in this case.
#xferlog_std_format=YES
#
# You may change the default value for timing out an idle session.
#idle_session_timeout=600
#
# You may change the default value for timing out a data connection.
#data_connection_timeout=120
#
# It is recommended that you define on your system a unique user which the
# ftp server can use as a totally isolated and unprivileged user.
#nopriv_user=ftpsecure
#
# Enable this and the server will recognise asynchronous ABOR requests. Not
# recommended for security (the code is non-trivial). Not enabling it,
# however, may confuse older FTP clients.
#async_abor_enable=YES
#
# By default the server will pretend to allow ASCII mode but in fact ignore
# the request. Turn on the below options to have the server actually do ASCII
# mangling on files when in ASCII mode.
# Beware that on some FTP servers, ASCII support allows a denial of service
# attack (DoS) via the command "SIZE /big/file" in ASCII mode. vsftpd
# predicted this attack and has always been safe, reporting the size of the
# raw file.
# ASCII mangling is a horrible feature of the protocol.
#ascii_upload_enable=YES
#ascii_download_enable=YES
#
# You may fully customise the login banner string:
#ftpd_banner=Welcome to blah FTP service.
#
# You may specify a file of disallowed anonymous e-mail addresses. Apparently
# useful for combatting certain DoS attacks.
#deny_email_enable=YES
# (default follows)
#banned_email_file=/etc/vsftpd.banned_emails
#
# You may restrict local users to their home directories. See the FAQ for
# the possible risks in this before using chroot_local_user or
# chroot_list_enable below.
#chroot_local_user=YES
#
# You may specify an explicit list of local users to chroot() to their home
# directory. If chroot_local_user is YES, then this list becomes a list of
# users to NOT chroot().
# (Warning! chroot'ing can be very dangerous. If using chroot, make sure that
# the user does not have write access to the top level directory within the
# chroot)
#chroot_local_user=YES
#chroot_list_enable=YES
# (default follows)
#chroot_list_file=/etc/vsftpd.chroot_list
#
# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
#ls_recurse_enable=YES
#
# Customization
#
# Some of vsftpd's settings don't fit the filesystem layout by
# default.
#
# This option should be the name of a directory which is empty. Also, the
# directory should not be writable by the ftp user. This directory is used
# as a secure chroot() jail at times vsftpd does not require filesystem
# access.
secure_chroot_dir=/var/run/vsftpd/empty
#
# This string is the name of the PAM service vsftpd will use.
pam_service_name=vsftpd
#
# This option specifies the location of the RSA certificate to use for SSL
# encrypted connections.
rsa_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
# This option specifies the location of the RSA key to use for SSL
# encrypted connections.
rsa_private_key_file=/etc/ssl/private/ssl-cert-snakeoil.key

new computer from boxes, does not install nvidia driver
Booted from USB then ran YaST, I am new with OpenSuse but have two times before installed OpenSuse on fresh HDD's and Nvidia cards with ease.

The symptoms are like when I switched from a GTX 640 that only has mother board power to the GTX 750 Ti and needed power that I did not connect at first. Until I added extra power to the graphics card I only got a single low res VGA output. This 750 card definitely has power but still can only provide single low res to VGA output.

Terminal (dmesg) ......The NVIDIA GPU 0000:01:00.0 (PCI ID: 10de:1380)installed in this system is not supported by the 304.125 NVIDIA Linux driver release. Please see 'Appendix A - supported NVIDIA GPU Products' in this release's README, available on the Linux driver download page at www.nvidia.com. .... None of the VVIDIA graphics adapters were initialized!

Terminal (uname -r) 3.16.7-21 -default [OpenSuse version]

Terminal (/sbin/lspci) VGA Compatible controller: Nvidia Corporation GM107 [GeForce GTX 750 Ti] (rev 02)

have tried:
1. different power cables to graphic card
2. two GTX 750 Ti cards, neither work.
3. re-installed OpenSuse
4. removed card and mother board can run two monitors in high res. DVI cables are new and work. Monitors (4) are all AOC i2367 and working.

5. added to repository 'bumblebee' which contains NVIDIA drivers and tried rebooting. I am not good at repositories yet. However, I didn't need to do this twice before on new installs with NVIDIA cards.

6. downloaded from www.geforce.com file:///home/shark/Downloads/NVIDIA-Linux-x86_64-346.72(1).run but when I run it error, "The file /home/shark/Downloads/NVIDIA-Linux-x86_64-346.72(3).run was opened with UTF-8 encoding but contained invalid characters."It is set to read-only mode, as saving might destroy its content.
Either reopen the file with the correct encoding chosen or enable the read-write mode again in the menu to be able to edit it."

Hardware list: Asus H81M-E motherboard, i5 4460 CPU, 550W power, Asus GeForce GTX 750 Ti graphic card,

Note: two graphic cards on hand, both work in another OpenSuse computer.

I am just learning Linux so I need simple step by step instructions.

Thank you in advance.

I first did the "try it", running it from the CD. I had the option to install from there and did. I cannot download any thing. My user name is John and there are 5 dots in the password space? My version is: ubuntu 14.04 lts. I was not able to change the root to read-write so I could change the password. Nothing worked unbuntu does connect to my wifi.
I'm a real newbie but what I 've tried in ubuntu has impressed me.
Help please