Do you hate how Centos 7 defaults to allocating most of your valuable space to /home even though it is a production server? Here is a quick guide on how to take back that space live, while online (of course make sure you have backups just in case something goes wrong!): First we will reduce our home dir by 100G: lvreduce -L -100G /dev/mapper/centos-home WARNING: Reducing active and open logical volume to ........

Before getting into the output here is my typical experience with SMART, there is what I call a "bad disk" with pending and uncorrectable sectors that cannot be reallocated. It has caused a kernel panic and system crash repeatedly as we can see from the logs. But SMART says it has "PASSED" its self assessment. SMART is still useful to me but it is more about looking at Current_Pending_Sector. Any time I have had anything but 0 for that attribute it........

#if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2 tar -jxvf ffmpeg-3.3.2.tar.bz2 cd ffmpeg-3.3.2/ ./configure --disable-yasm install prefix /usr/local source path ........

pip install obfsproxy /usr/lib/python2.6/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning. InsecurePlatformWarning You are using pip version 7.1.0, however version 8.1.1 i........

Press F2, you wouldn't know this because like most new computers, it doesn't announce the required key unless you enable it from the BIOS. ........

Hit Alt + F10 before the system boots and you'll boot into the recovery drive and be able to restore your system, of course note that all of your data will be wiped out.........

Another new drive bad from the start: Jun 2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen Jun 2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error Jun 2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC } Jun 2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........

This is just trying to read 5GB off the drive with dd and the drive initially tested ok but shortly after I wondered why I was seeing 2MB/s read speeds. Notice the "current_pending_sector", anytime I've seen it at anything above 0 even with no other bad fields/attributes, it means the drive is bad. ata1.00: exception Emask 0x0 SAct 0x3 SErr 0x0 action 0x0 ata1.00: irq_stat 0x40000008 ata1.00: failed command: READ FPDMA QUEUED ata1.00: cmd 60/00:00:........

Here's a proven example of what a bad hard drive can do, it was technically functioning OKin a RAID array but the system became extremely low and the load become high and IOWAIT was even higher and I always thought it was a bad application. The truth is that this failing 1TBHitachi has slowly gotten worse and caused huge slowdowns, (eg. 100% load on Thunderbird waiting for e-mails to load etc..). After swapping it out, tabs change instantly, emails are not lagged, and........

Even in new versions of Ubuntu this happens but for me I found out it was because of one feature under "Power Management". I had "Spindown hard disks when possible" ticked, after disabling that, my computer wakes up from suspension every time now. So if your computer won't unsuspend with any version of Ubuntu/*Nix try disabling the spin down hard disk option as it's obviously the culprit for many situations.........

I like dd, although it only reads it, usually a read test of the entire disk will uncover if your hard drive is bad in some parts. This is a good thing to do at least once a month, a lot of times bizarre program behavior, laginess and crashing/unnmounting problems etc.. are due to a failing disc and SMART won't know it or indicate a problem: We must also remember there's never a guarantee, I've found that ever since we moved to larger and more platters per drive with 1TB drives........

I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior: === START OF INFORMATION SECTION === Device Model: WDC WD20EARS-00MVWB0 Serial Number: WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity: 2,000,398,934,016 bytes Device........

I had one of these shipped and it was not recognized when plugged in, here's what a dead drive looks like (I assume it's teh circuit board which is dead): ata1: link is slow to respond, please be patient (ready=0) ata1: softreset failed (device not ready) ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) ata1: link online but device misclassified, retrying ata1: link is slow to respond, please be patient (ready=0) ata1: softreset f........

I don't have a solution other than to use rsync, I used diff on about 1.7TB of data which includes hundreds of thousands if not millions of small files to ensure nothing was missing or corrupt. diff didn't even get past the first large directory without spitting that error out. Keep in mind I used "diff -r" because that means recursive, otherwise it wouldn't compare all files and subdirectories and would be a false way of doing it.........

kernel 2.6.27.54 Fusion MPT base driver 3.04.07 Copyright (c) 1999-2008 LSI Corporation Fusion MPT SPI Host driver 3.04.07 mptbase: ioc0: Initiating bringup mptbase: ioc0: WARNING - Unexpected doorbell active! mptbase: ioc0: ERROR - Doorbell ACK timeout (count=4999), IntStatus=80000001! mptbase: ioc0: ERROR - Diagnostic reset FAILED! (102h) mptbase: ioc0: WARNING - NOT READY! mptbase: ioc0: ERROR - didn't initialize proper........

I think this will be useful to others because I have a server that kept crashing mysteriously during intense disk usage/RAID checks. It would only crash during the weekly RAID integrity check. ThenI noticed during a reboot that not all CPUs were being brought up, as a result this actually creates much higher temperatures with the output I got from sensors, just booting the system produced higher than normal temperatures. You can imagine that a full blown RAID check........

CPU/Kernel/MB/RAID problem? Jan 5 12:45:05 testbox kernel: [653298.890004] BUG: soft lockup - CPU#0 stuck for 61s! [hal-acl-tool:4168] Jan 5 12:45:05 testbox kernel: [653298.890005] Modules linked in: vmnet vmci vmmon binfmt_misc drbd video output input_polldev ocfs2_stackglue ocfs2_dlmfs ocfs2_dlm ocfs2_nodemanager configfs k8temp hwmon_vid lp snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi........

crontab not working It is running as user Apache I've tried 0 0 * * * (which means midnight 00:00) and it does run at midnight but also 13:25 for some reason? 25 0 * * * with this it runs at 00:25 but again also at 13:25 Solution - Restart the Cron Service (especially if you changed your time/timezone) *Update I had a suspicion that changing the timezone a few weeks ago caused this. I restarted lhe cron service and the problem h........

hdparm -B 255 /dev/sdb /dev/sdb: setting Advanced Power Management level to disabled HDIO_DRIVE_CMD failed: Input/output error The one thing you can do though is to set hdparm spindown time lower (it doesn't seem to work that well). -S set standby (spindown) timeout hdparm -S 251 /dev/sda /dev/sda: setti........

Let the numbers speak for themselves, from what I read the Load_Cycle_Count which is very high (more than 500,000/half a million times) is the number of head parks. What a stupid"Green" design and design flaw which will probably mean an early life for the drive. This is almost as silly as Seagate's new reputation for BSY/poor quality disks since the 7200.11 series. To make it worse this is also when Western Digital introduced "Advanced Format" o........

This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned. I didn't blame Seagate for their past issues until now. This hard drive has hardly been used and has not even been powered on for a year according to SMART. Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.11 Device........

Seagate Inventory/Firmware Check I heard about this issue a long time ago but never looked into it. I figured I wasn't affected since my 500GB drives were running for so long. I've been using Seagate's since 2002 and to this day all of the drives I have are alive from Seagate. *Update the bad news is that I realize one of my 500GB's is about to die, it's not even a year old, but is also not affected by the recall according to Seagate! Seagate Inventory/Firm........

PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist: [code:1:1fd0f3abbe] if (!file_exists($OPENSSL)) { //echo "ERROR: OPENSSL $OPENSSL not foundn"; }[/code:1:1fd0f3abbe] I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........

Roxio Easy Media Creator "Could not complete last comma[b:2e4e25672a]"Could not complete the last command because: Unknown error"[/b:2e4e25672a] When I try to burn an .iso image by double clicking it and allowing Roxio to open up "Disc Copier" I get a bunch of those messages. It's annoying and not really awe inspiring!........

When trying to even cd or ls the mounted OCFS2 partition it crashes. Ithink this is a combination of VMWare Server's problem and the way I mounted and symlinked to it. More than anything this shows the problem and lack of forsight with VMWare, but also that OCFS2 is easily crashed if you do strange things. Output of /var/log/messages for OCFS2 Apr 10 15:57:45 localhost kernel: [84331.691258] Modules linked in: vmnet vmci vmmon ocfs2_stac........