Occasionally my whole screen locks up and I cannot even swith to the console and I find this in my syslog:
*-display
description: VGA compatible controller
product: Mullins [Radeon R3 Graphics]
vendor: Advanced Micro Devices, Inc. [AMD/ATI]
 ........
mysql reset root password.
Oops I can't remember my MySQL root password!
[root@centos7test etc]# mysql -u root -p
Enter password:
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
First we need to stop mariadb:
systemctl stop mariadb
Now we need to restart it with skip-grant-tables whic........
debug1: Local connections to LOCALHOST:18006 forwarded to remote address 192.168.1.93:8006
debug1: Local forwarding listening on 127.0.0.1 port 18006.
debug1: channel 0: new [port listener]
debug1: Local forwarding listening on ::1 port 18006.
bind: Cannot assign requested address
What we are seeing is that we can't listen on an IPV6 address of ::1. We need to tell SSH to stop using IPV6 so we'll edit ssh_config to take care of this issue........
In Debian a lot of times SSH disables the root user to login by password by default. This means you will get an authentication failure as if you typed in the wrong password.
The logs also indicate the password is wrong but what is often the case is in the config file
Check /etc/ssh/sshd_config
cat /etc/ssh/sshd_config|grep -i permitrootlogin
Make sure it says:
PermitRootLogin yes
If not change it and restart SSH........
Intel VT-X is enabled in Virtualbox but it doesn't seem to pass through the needed vmx extension despite the following variables on the host confirming it is enabled:
cat /sys/module/kvm_intel/parameters/nested
Y
cat /sys/module/kvm_intel/parameters/ept
Y
OVF Tool: Disk progress: 99%
OVF Tool: Transfer Completed
OVF Tool: Powering on VM: Embedded-vCenter-Server-Appliance-
OVF Tool: Task p........
#mount the VCSA DVD
mount /dev/sr0 /mnt/cd
#alternatively you could mount the iso directly
mount -o loop vcsa.iso /your/mount/path
#for this purpose we are using the CLI installer on Linux
cd /mnt/cd/vcsa-cli-installer/lin64
#no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file
./vcsa-deploy
Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
Essentially a program I was running for mining did not terminate properly with Ctrl+C it is listed as defunct and cannot be killed, kernel is tainted and normal tricks to disable the port are impossible the dev and sys entries for the device cannot be browsed or interacted with in any form without a lockup of the request. The only solution is to reboot due to the kernel taint as far as I can find so far.
[1130246.811056] INFO: task minerd:21861 blocked for more th........
This is a 8TB Seagate external USB 3.0 device apparently newer kernels use a module called "UAS" instead of "USB Storage" which causes issues as a lot of devices are not properly supported in UAS mode by the kernel driver. The solution some say is to disable UAS specifically for your USB device but I'd rather just disable UAS altogether.
Solution blacklist UAS: *do not do this it does not work and just causes your USB 3.0........
This was a surprising bug but I unplugged all drives for an array md127. At first it was just 1 drive and mdadm seemed to notice this. I unplugged the second drive taking the array offline but mdadm did not realize it was offline and still showed a non-existent disk as being part of it. This created problems trying to unmount it or even to stop this array with mdadm freezing.
As for how to fix it I can only think of making sure you are not in a mounted path of........
I created a new partition table on a newly plugged in device and it caused fdisk to hang (even force kill does not work). It also may be a bad drive or some other issue because fdisk -l hangs after the first 2 HDDs (totaly of 8 HDDs on this system):
[1232879.903596] INFO: task fdisk:27176 blocked for more than 120 seconds.
[1232879.903607] Tainted: P&nbs........
This happened while an mdadm array was syncing, all access from writing a new blank file to opening a small .txt file was very slow:
[222117.312078] kjournald starting. Commit interval 5 seconds
[222117.685060] EXT3-fs (md0): using internal journal
[222117.685096] EXT3-fs (md0): mounted filesystem with ordered data mode
[222122.376847] kjournald starting. Commit interval 5 seconds
[222122.602825] EXT3-fs (md2): using internal jour........
I used the matching 8.3.13 utilities and it didn't work but strangely the newer 8.3.16 which makes DRBD complain works just fine.
GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51
0: cs:SyncSource ro:Secondary/Primary ds:UpToDate/Inconsistent A r-----
ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:5236960
&am........
On the same OS with the same kernels basically I cannot boot FreeBSD installer, I believe the issue is the host CPU.
One host runs an Intel and works, while an Opteron 2373 does not work despite suggestions from this thread: http://149.20.54.209/showthread.php?t=36761
I've tried cpu options like "kvm64" "Opteron_G3" and none........
LSi Megaraid
At first it was configured as a RAID 0, then I deleted the Virtual Disk Group.
I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing.
To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group. In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........
Here is a quick script that works on most Centos versions to disable the virus/SELinux from blocking basic functionality.
The first echo 0 statement disables SELinux instantly but it will still be enabled on reboot.
The second line disables it permanently.
#!/bin/bash
#disable SELinux Immediately
echo 0 > /selinux/enforce
#disable SELinux Permanently
sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config........
high IO wait
424 root 39 19 1900 848 552 D 0.0 0.0 0:00.91 updatedb
root 424 0.0 0.0 1900 848 ? DN Mar11 0:00 /usr/bin/updatedb -f sysfs?rootfs?bdev?proc?cpuset?binfmt_misc?debugfs?sockfs?usbfs?pipefs?anon_inodefs?futexfs?tmpfs?inotifyfs?eventp........
*Remember to restart spamassassin after all of this.
DCC
wget http://www.dcc-servers.net/dcc/source/dcc.tar.Z
tar -zxvf dcc.tar.Z
cd dcc-1.3.138/
./configure;make;make install
#enable DCC, uncomment the line that disables it near the top
vi /etc/mail/spamassassin/v310.pre
pyzor
wget http://sourceforge.net/projects/pyzor/files/pyzor/0.5.0/pyzor-0.5.0.tar.gz/down........
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........
Jan 16 04:02:03 centosbox syslogd 1.4.1: restart.
Jan 16 04:07:34 centosbox kernel: INFO: task updatedb:20771 blocked for more than 300 seconds.
Jan 16 04:07:34 centosbox kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jan 16 04:07:34 centosbox kernel: updatedb D F78BE050 6476 20771 20766&n........