tag:blogger.com,1999:blog-18935970424350358892024-02-02T02:25:47.079-08:00Command Center#!/bin/GREPing a '[programmer][sysadmin]' with Killer SkillzSkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comBlogger1679125tag:blogger.com,1999:blog-1893597042435035889.post-24383629983191676862014-06-26T11:18:00.001-07:002014-06-26T11:18:17.222-07:00HOW TO FIGURE OUT WHAT IS CAUSING AN APACHE SEGMENTATION FAULT
Having an apache segmentation fault on your server can drive you crazy trying to solve it… So, I’m gonna explain you how I figured out what was causing the last apache segfault I had.
My server was running under Debian Squeeze, with Apache 2.2 and PHP 5.3, and I got randomly segmentation faults:
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[Jun 08 17:38:07 2012] [notice] child pid 5646 exit signal Segmentation fault (11SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-57086850342940365562014-04-11T13:34:00.002-07:002014-04-11T13:34:53.515-07:00Certificate issue on remote desktopError:
he remote computer could not be autherticated due to problems with its security certificate. it may be unsafe to proceed.
Solution:
Windows Vista/2008+ secures the remote connection with a self signed certificate. This certificate only exists on the server and until you import it on your machine, you will get a warning.
How to fix -
You can view the certificate then import it to SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-31296480928737777742014-03-25T12:02:00.002-07:002014-03-25T12:02:20.569-07:00Mounting a remote linux directory onto a windows machine for editing files
Introduction
In many cases it can become cumbersome to transfer files to and from a
droplet. Imagine a development usage scenario where you are coding apps
remotely and find yourself uploading a script repeatedly to your
virtual server to test. This can become quite a hassle in a very short
period of time. Luckily there is a way to mount your VPS file system to
your local computer soSkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-79145940201572173632013-12-20T13:33:00.002-08:002013-12-20T13:33:40.320-08:00Configuring postfix to forward all email to a smtp gateway
Introduction
Suppose you want all your web servers to locally send all email (maybe from your contact forms, or whatever)
to a real smtp gateway. If you're running postfix as your mta, this is quite easily to achieve.
Configuration
In your main.cf file (usually /etc/postfix/main.cf or /usr/local/etc/postfix/main.cf), specify your transport maps:
view plaincopy to clipboardprint?
SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-26736396722366899342013-12-20T13:30:00.001-08:002013-12-20T13:30:03.390-08:00Volts / Watts / Amps Converter
How to use this tool:
Watts = Amps x Volts
Watts is also known as volt-amps and is typically used in conjunction with AC power circuits. Fill in any of the two fields to find the value of the third.
Example 1
You have a 12 Volt power supply that delivers 1 Amp of current. Fill in the Volts and Amps fields to find the Watts.
Example 2
The AC24-40 power supply is a 24V AC power supply that SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-89800152441171724752013-09-12T08:37:00.000-07:002013-09-12T08:37:26.614-07:00How to detect the physical connected state of a network cable/connector?
You can use ethtool:
$ sudo ethtool eth0
Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-3411775271959994492013-08-30T11:02:00.005-07:002013-08-30T11:02:55.608-07:00mount error(115): Operation now in progress ... CIFS VFS: cifs_mount failed w/return code = -115Trying to mount a CIFS path in Ubuntu and getting:
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mount error(115): Operation now in progress
First thing to try is to look into /var/log/syslog:
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Feb 9 14:08:29 ldap kernel: [143452.140157] CIFS VFS: Error connecting to socket. Aborting operation
Feb 9 14:08:29 ldap kernel: [143452.140492] CIFS VFS: cifs_mount failed w/return code = -115
Socket SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-77546024669643738882013-08-30T11:02:00.001-07:002013-08-30T11:02:04.082-07:00How do maintain a constant mac address on bonded NICs?In 10.04 this consistenlty create bond0 with the mac address from eth0.
with 12.04, the mac address used appears to be random - sometimes it's the address from eth0, sometimes it's the address from eth1.
After trying MakOwner's solution to no avail, I think I solved it for my case.At bootup I noticed in dmesg that eth1 was coming up before eth0, probably due to some unpredictable hardware SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-35458806794428858932013-08-26T23:41:00.000-07:002013-08-26T23:44:51.999-07:00ffmpeg Cheat Sheet
Video Size and Aspect Ratios
iPhone 3 (480x320):
Name
Size
Aspect
Wide 16:9
480x270
16:9
Old TV 4:3
427x320
4:3
Wide 16:9 /16
480x272
16:9
Old TV 4:3 /16
432x320
4:3
iPhone 4 (960x640):
Name
Size
Aspect
Wide 16:9
SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-31987821869590719032013-08-22T14:58:00.003-07:002013-08-22T14:58:56.575-07:00browser agents
Firefox
Mozilla/5.0 (Windows NT 6.1; rv:10.0.2) Gecko/20100101 Firefox/10.0.2
Chrome
Mozilla/5.0 (Windows NT 6.1) AppleWebKit/535.19 (KHTML, like Gecko) Chrome/18.0.1025.162 Safari/535.19
Safari
Mozilla/5.0 (Windows NT 6.1) AppleWebKit/534.50 (KHTML, like Gecko) Version/5.1 Safari/534.50
Opera
Opera/9.80 (Windows NT 6.1; U; en) Presto/2.9.168 Version/11.50
IE
Mozilla/5.0 (compatible; SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-66375785454047430442013-08-18T01:02:00.000-07:002013-08-18T01:02:20.323-07:00yum The requested URL returned error 404ERROR:
[Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404"
Solution:
#yum clean all
SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-54918772815835175362013-07-26T16:29:00.002-07:002013-07-26T16:29:48.643-07:00What is this .nfs file and why can I not remove it?Under linux/unix, if you remove a file that a currently running process still has open, the file isn't really removed. Once the process closes the file, the OS then removes the file handle and frees up the disk blocks. This process is complicated slightly when the file that is open and removed is on an NFS mounted filesystem. Since the process that has the file open is running on one machine (SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-67537648700103588502013-07-20T20:20:00.003-07:002013-07-20T20:20:45.632-07:00HOWTO: add disk to VMware Ubuntu guest without reboot using LVM
This howto is mostly built on the great tutorial available athttp://www.comnetslash.com/…hout-reboot/. My spot tries to be more Ubuntu and LVM specific. This manual was tested on Ubuntu 9.04 (jaunty) Server edition guest OS.
Add Virtual Hard Disk
A new hard disk can be added easily to a running virtual machine in VMWare Infrastructure Web Access by clicking Add Hardware and followingSkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-11843411548473695582013-06-20T08:13:00.003-07:002013-06-20T08:13:44.933-07:00Stop Ubuntu / Debian Linux From Deleting /tmp Files on Boot
Q. I know /tmp as it named is a temporary dircory, Debian policy is to clean /tmp at boot. However, I'd like to configure my Ubuntu Server to stop deleting files from /tmp on boot due to custom configuration issue. How do I configure behavior of boot scripts to stop deleting files on boot?A. Users should not store files in /tmp, use /home or other partition, if you would like to keep the SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-90021900868209428412013-06-11T08:18:00.002-07:002013-06-11T08:18:43.900-07:00IP_CONNTRACK: TABLE FULL, DROPPING PACKET
Last week, I found myself with a server under low load, but it couldn’t make or receive network connections. When I ran dmesg, I found the following line repeating over and over:
ip_conntrack: table full, dropping packet
I’d seen this message before, but I headed over to Red Hat’s site for more details. It turns out that the server was running iptables, but it was under a SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-77884486294667471772013-05-23T22:14:00.000-07:002013-05-23T22:14:02.069-07:00 Remount using fstab entries
7.1.2. Remounting the File Systems
After adding the usrquota and/or grpquota options, remount each file system whose fstab entry has been modified. If the file system is not in use by any process, use one of the following methods:
Issue the umount command followed by the mount command to remount the file system.(See the manpage SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-63112362924873516232013-04-29T14:29:00.003-07:002013-04-29T14:29:24.621-07:00Error : ” child pid exit signal File size limit exceeded (25) in Apache ” Resolution
Many times if you find apache processes dying in the top process list or apache failing to start completely then one of the reasons could be a log file larger than 2Gb , which is indicated by the below error in the apache error logs :child pid XXXX exit signal File size limit exceeded (25)
where XXXX is process id for the process which is failing and generating the error in the error log.
To SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-38109165974322455022013-04-22T16:16:00.001-07:002013-04-22T16:16:56.966-07:00Error ID: 0x800CCC0F
Some of the possibilities for this error are as follows :
1. Make sure your e-mail settings are correct: Mail Server, Username, and Password.
2. Clear messages in the outbox folder
3. Delete large emails, if any, in webmail.
4. Adjust mail server timeouts.
5. Your antivirus program has e-mail protection enabled, which checks the mail as it comes in from your Post Office Protocol (POP) SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-73256837727198566332013-04-15T14:04:00.003-07:002013-04-15T14:04:52.043-07:00What is a Glue Record?
Glue Records
This article offers a definition of a Glue Record, a description of why a Glue Record is need and how they are resolved through DNS, and how to create a Glue Record through the CloudAccess.net Client Area.
What is a Glue Record?
Why are Glue Records needed?
How to create a Glue Record
What is a Glue Record?
A Glue Record is the IP Address of a name server at a domain name SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-3123172291388782992013-04-15T11:17:00.003-07:002013-04-15T11:17:39.272-07:00MySQL 4.1+ using old authentication
When I was working with XAMPP in Ubuntu and asked write PHP script to connect to remote MySQL server which is using PASSWORD hash function to save the password for user, and I found following error.
Warning: mysql_connect() [function.mysql-connect]: Premature end of data (mysqlnd_wireprotocol.c:554) in path/to/the/file/where/connection/script/is/written/Warning: mysql_connect() [SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-83037978157851065452013-03-25T14:51:00.002-07:002013-03-25T14:51:31.459-07:00CentOs - make time zone chagne permanent
1. Edit /etc/sysconfig/clock
* ZONE="US/Central" <-this br="" change="" is="" the="" to="" value=""> * UTC=false
* ARC=false
2. run tzdata-update
3. run /etc/init.d/ntpd restart </-this>
REFERENCES
http://speeves.erikin.com/2009/05/centos-make-time-zone-chagne-permanent.html
SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-47360141914010954122013-03-22T08:42:00.002-07:002013-03-22T08:42:32.462-07:00Change Default Editor for visudo in Ubuntu
Ubuntu and Debian use the alternatives system to maintain the symbolic links for programs. When you first run visudo, it will prompt a list of editors for you to choose from. Unfortunately, it doesn’t tell you how to change that setting again. The mostly happend situation is: you set it to “nano” at first, and can’t change it to “vi” at a later time.
Here is the command to bring up that SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-11230839194369203252013-03-12T13:56:00.000-07:002013-03-12T13:56:25.600-07:00How to enable multiple remote connection for windows server 2012
By default Windows 2008 only allows a user one single session over RDP. While in some instances this can be quite handy, if like me, you have multiple developers working on a single server, your frustration from being randomly logged out by a colleague can come to the boil. Quick and easy solution.
Log in to your Windows 2008/Windows 2008 R2 machine (it can be via RDP if you wish)
Open up&SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-82094088484533320142013-02-28T12:50:00.003-08:002013-02-28T12:50:39.796-08:00How do I change the DRAC root password?
Step by step for iDRAC6:
Log in as root
Select Remote Access from the left-hand menu
Select the Network/Security tab
Select the Users tab
Click the number “2” hyperlink in the User ID column
Select Configure User and click Next
Select Change Password and fill out the following password fields
Click Apply
REFERENCES
http://SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.comtag:blogger.com,1999:blog-1893597042435035889.post-75490335585481370852013-02-27T09:55:00.001-08:002013-02-27T09:55:33.680-08:00Using the Local Default Gateway with a Windows VPN Connection
To stay connected while I’m out of the office or travelling, I use a VPN connection from my laptop to a Windows Server. And while the benefit of being able to quickly and securely access my documents and other files on the server over any Internet connection is nice, the drawback is that all Internet traffic gets routed through the default gateway on the remote SkyHihttp://www.blogger.com/profile/04817086377675648963noreply@blogger.com