Many server admins would like to check what port speed their server was configured by their host provider. If you paid for a 10Mbs or 1000Mbs connection, you definitely want to check on its correct provisioning.
Log into your server via putty and enter this command.
STEPS
root@server [~]# mii-tool
You will get a response like this example.
eth0: 100 Mbit, full duplex, link ok
mii-tool Command variables.
mii-tool [-v, --verbose] [-V, --version] [-R, --reset] [-r, --restart] [-w, --watch] [-l, --log] [-A, --advertise=media,...] [-F, --force=media] [interface ...]
Written by admin on August 22nd, 2008 with comments disabled.
Read more articles on How To and Linux.
Our intrusion detection software picked up the start of a dictionary attack targeting our pop3 or email server coming from the Layeredtech server provider.
Time: Sat Aug 9 19:22:43 2008 -0400
IP: 72.232.183.242 (US/United States/242.183.232.72.static.reverse.ltdomains.com)
Failures: 5 (pop3d)
Interval: 240 seconds
Blocked: Yes
Log entries:
Aug 9 19:21:16 pop3d: LOGIN FAILED, user=test, ip=[::ffff:72.232.183.242]
Aug 9 19:21:52 pop3d: LOGIN FAILED, user=test, ip=[::ffff:72.232.183.242]
Aug 9 19:21:57 pop3d: LOGIN FAILED, user=web, ip=[::ffff:72.232.183.242]
Aug 9 19:22:36 pop3d: LOGIN FAILED, user=test, ip=[::ffff:72.232.183.242]
Aug 9 19:22:41 pop3d: LOGIN FAILED, user=test, ip=[::ffff:72.232.183.242]
Whois 72.232.183.242 you might ask?
Why it is the crappy dedicated server provider Layeredtech.
OrgName: Layered Technologies, Inc.
OrgID: LAYER-3
Address: 5085 W Park Blvd
Address: Suite 700
City: Plano
StateProv: TX
PostalCode: 75093
Country: US
Written by admin on August 10th, 2008 with comments disabled.
Read more articles on Hacker and ModSecurity.
There are a few ways to see what version of Centos your server has installed.
Steps
1) While logged in as root, enter the following commands.
cat /etc/redhat-release
This should produce a response like this:
CentOS release 5.2 (Final)
2) Another method is to enter the following command:
rpm -qa | grep centos
This should produce results like this:
root@server [~]# rpm -qa | grep centos
procmail-3.22-17.1.el5.centos
comps-extras-11.1-1.1.el5.centos
basesystem-8.0-5.1.1.el5.centos
gdm-2.16.0-46.el5.centos
pm-utils-0.99.3-6.el5.centos.19
yum-fastestmirror-1.1.10-9.el5.centos
specspo-13-1.el5.centos
rhgb-0.16.4-8.el5.centos.1
nss-3.11.99.5-2.el5.centos
centos-release-notes-5.2-2
desktop-backgrounds-basic-2.0-40.el5.centos
anacron-2.3-45.el5.centos
pango-1.14.9-3.el5.centos
kdelibs-3.5.4-16.el5.centos
system-config-date-1.8.12-3.el5.centos.2
gnome-session-2.16.0-6.el5.centos
gnome-desktop-2.16.0-1.el5.centos.1
redhat-logos-4.9.99-8.el5.centos
redhat-artwork-5.1.0-26.el5.centos
redhat-lsb-3.1-12.3.EL.el5.centos
pirut-1.3.28-13.el5.centos
httpd-manual-2.2.3-6.el5.centos.1
filesystem-2.4.0-1.el5.centos
mod_ssl-2.2.3-6.el5.centos.1
ntp-4.2.2p1-8.el5.centos.1
nss-tools-3.11.99.5-2.el5.centos
gzip-1.3.5-10.el5.centos
busybox-1.2.0-4.el5.centos
initscripts-8.45.19.EL-1.el5.centos.1
firstboot-tui-1.4.27.3-1.el5.centos
firstboot-1.4.27.3-1.el5.centos
crash-4.0-5.0.3.el5.centos
Deployment_Guide-en-US-5.2-9.el5.centos
kdebase-3.5.4-18.el5.centos
yum-protectbase-1.1.10-9.el5.centos
xorg-x11-proto-devel-7.1-9.el5.centos
setuptool-1.19.2-1.el5.centos
centos-release-5-2.el5.centos
yum-3.2.8-9.el5.centos.2.1
bluez-utils-3.7-2.el5.centos
httpd-2.2.3-6.el5.centos.1
firefox-3.0-0.beta5.6.el5.centos
3) To check your Kernel version, you could enter this command.
uname -a
Written by admin on June 25th, 2008 with comments disabled.
Read more articles on Centos and How To.
Yum is word that may inspire fear in hearts of many noobie server admins because they don’t understand what it does and fear it make break their server if used.
Yum stands for “Yellow Updater, Modified” and is similar to commands apt-get and up2date in function.
Here are some common Yum commands used while you are logged in as root.
# yum upgrade
# yum update
# yum install bind
Yum usage:
yum [options] <update | upgrade | install |
info | remove | list |clean | provides |
search | check-update | groupinstall |
groupupdate | grouplist>
Yum Options
-c [config file] - specify the config file
to use
-e [error level] - set the error logging
level
-d [debug level] - set the debugging level
-y answer yes to all questions
-t be tolerant about errors in package
commands
-R [time in minutes] - set the max amount of
time to randomly run in.
-C run from cache only - do not update the cache
--installroot=[path] - set the install root
(default '/')
--version - output the version of yum
-h, --help this screen
Written by admin on June 24th, 2008 with comments disabled.
Read more articles on Centos and Linux.
