This guide assumes you have a working Postfix server and want it to sign with DKIM.
There are a few things we have to understand to make all of this work though, which require you to be familiar with DNS as well.
1.) Install OpenDKIM
apt install opendkim
systemctl enable opendkim
2.) Edit /etc/opendkim.conf
Syslog yes
SyslogSuccess yes
Mode&nbs........
apt install tftpd-hpa
#change TFTP_ADDRESS to by setting address to 192.168.1.1:69 or the IP you need, otherwise it will listen on all IPs and interfaces which could be a security risk.
# edit /etc/default/tftpd-hpa
TFTP_USERNAME="tftp"
TFTP_DIRECTORY="/srv/tftp"
TFTP_ADDRESS="192.168.1.1:69"
TFTP_OPTIONS="--secure"........
Have you ever tried mounting a partition that you exists but you get this error?
mount: /mnt: can't read superblock on /dev/sda1.
The superblock in this example was bad because the physical disk had corruption and bad blocks/sectors. However, the data was generally accessible and you can always try this trick below (with caution and no warranty).
This is specifically for filesystems that place superblocks in multiple locations, which........
This is a weird issue as sometimes when upgrading or even migrating, this could happen and the reason is simple but maybe not 100% obvious at first.
You will find that your GUIdoesn't load and most services fail to start, even logind
Here are some errors you may see:
Mar 13 22:22:23 rttbox systemd-logind[2892]: Failed to connect to system bus: No such file or directory
Mar 13 22:22:23 rttbox systemd-logind........
Let's say you have a directory /mnt/raid which has files and directories inside it, but nothing is mounted to it.
Then you mount a block device such as /dev/sdh to /mnt/raid
Even though /mnt/raid has files and directories there, you can only see the mounted contents of /mnt/raid.
How do we access the original contents?
Just do a bind mount of the root filesystem to another location.
mkdir /bindmount
mount --bind / /b........
In this example we install debian 10 with --variant=minbase which gives us a minimal/tiny install. Don't use variant if you want the full size install.
mkdir /tmp/deb10files
debootstrap --variant=minbase buster /tmp/deb10files/
Did you get an error?
debootstrap --variant=minbase buster /home/theuser/VMs/deb10files/
You'll get this error if you make a directory in your home........
1.) Create your EFI/ESP Partition
If you happen to have some free space on the drive already then this is easy, just create a new partition of at least 100M.
The nice thing about the EFI spec is that it must just be in the first 2.2TB of space so for most users, it means you can simply resize the last partition(downsize it by 100M) and then add an EFI partition at the end.
For example if you had this partition scheme:
/dev/sda1 = /........
This article about migrating to a CentOS 7 /8 RAID mdadm array has a lot of info but I wanted to focus specifically on what newer versions of CentOS 7 require to boot mdadm and what changes are necessary on CentOS 7.8+
CentOS 7 / 8 mdadm RAID booting requirements
This assumes you are chrooting into an existing install or using it to get a new deployment ready. However, these steps can........
This can be used on almost anything, since Gluster is a userspace tool, based on FUSE. This means that all Gluster appears as to any application is just a directory.
Applications don't need specific support for Gluster, so long as you can tell the application to use a certain directory for storage.
One application can be for redundant and scaled storage, including for within Docker and Kubernetes, LXC, Proxmox, OpenStack, etc or just your image/web/video files or even da........
This may be necessary if you have a VM or if for some reason you just want to be more efficient with your space and have the flexibility of changing your swap space at will.
What we mean is the ability to use a "swap file" or similar to the Windows "pagefile" that normally resides on the root or c: partition of Windows.
Here's all you have to do and then you to can have a single partiton with everything, including the swap file on the root partition if you........
1. Let's work from an environment where we can install Ansible on.
If you are using an older version of Linux based on Mint 18 or Ubuntu 16, you may want to get the PPA and get the latest version of Ansible that way:
sudo apt install gpg
sudo add-apt-repository ppa:ansible/ansible
sudo apt update........
There aren't too many simple guides that show you how to use commands to setup your USB or other drive as a normal bootable drive where you can easily boot custom kernels or whatever OS you would like.
1. Get the tools we need:
We install "syslinux" for MBR and "syslinux-efi" for EFI and "MBR" as we need a tool that embeds the actual MBR into our USB:
sudo apt install syslinux syslinux-efi mbr........
Usually if you get the grub boot loader and it doesn't show any boot options, it's because grub was not installed correctly and/or the partition that it is supposed to be on has changed or does not exist. It can also happen if you install Linux to one drive, but the boot loader to another by accident, whether EFI or MBR/Legacy mode.
You can normally fix your booting/bootloader/MBR/EFI it by chrooting into your root partition:
#become root
sudo su........
Just a quick note and warning is that if you are testing to see if EFIPXE booting works on a VM, MAKE SURE it actually works. For example Iinitially tested using my Distro's QEMU 2.5+dfsg-5ubuntu10.46 and ovmf BIOS firmware (OVMF supports EFI). However, I found on old versions of QEMU (like 2.5), EFIbooting with GRUB NEVER works so it may appear that you have made a mistake when everything is fine when you boot a physi........
Enable "cli" mode equivalent in JunOS
cli
Configure Mode
configure
So rather than going to the console on a Cisco switch and typing "enable" and then "conf t", the equivalent in JunOS is "cli" and "configure".
How Do You Apply Changes You've Made?
You can make all kinds of changes to the switch, but remember they are not........
It really seems limited in that it can mainly give you the things you would see on the physical unit such as load etc..
wget https://downloads.sourceforge.net/project/apcupsd/apcupsd%20-%20Stable/3.14.14/apcupsd-3.14.14.tar.gz?r=https%3A%2F%2Fsourceforge.net%2Fprojects%2Fapcupsd%2Ffiles%2Flatest%2Fdownload&ts=1598115866
tar -zxvf apcupsd-3.14.14.tar.gz
cd apcupsd-3.14.14
[root@somebox apcupsd-3.14.14]#
./conf........
/usr/libexec/qemu-kvm -enable-kvm -boot order=cd,once=dc -vga cirrus -m 4096 -drive file=~/23815135.img,if=virtio -usbdevice tablet -net nic,macaddr=DE:AD:BE:EF:D4:AB -netdev bridge,br=br0,id=net0
qemu-kvm: -usbdevice tablet: '-usbdevice' is deprecated, please use '-device usb-...' instead
access denied by acl file
qemu-kvm: bridge helper failed
[root@CentOS-82-64-minimal 23815135]# /usr/libexec/qemu-kvm -enable-kvm -boot order=cd,once=dc -vga cirrus -........
apt install software-properties-common
add-apt-repository ppa:deadsnakes/ppa
apt update
apt install python3-pip
apt install python3.7 curl gnupg python3.7-dev git
ln -s /usr/bin/python3.7 /usr/bin/python3
pip3 install numpy keras_preprocessing
curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add -
echo "deb [arch=amd64] http://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel........
Most newer distros inexplicably cause your NIC to have what Icall "random" non-standard name conventions because of systemd.
This is a big problem for many people and especially those running servers. Imagine that you have a static IPconfigured for ens33 but then the hard disk is moved to a newer system, the NIC could be anything from ens33 to enp0s1, meaning that manual intervention is required to go and update the NIC config file (eg. /etc/network/interfa........
This is caused because the user is running as qemu for virt-resize and if qemu does not have privileges to read from the source and write to the destination, it will fail with the below. So either change the uid of qemu or change the ownership of the source and target.
Solution:
export LIBGUESTFS_BACKEND=direct
virt-resize --expand /dev/sda2 /root/kvmtemplates/windows2019-eval-template.img /root/kvmguests/kvmkvmuser4515........
This is sure simple if you follow the guide but it took a lot of hacking around to make this work on Debian/Ubuntu!
Now before you ask why bother running wine and python, the reason is because Python executables are NOT cross-platform. If you run pyinstaller in Linux, that binary will only run on Linux and the same if you do it in Windows. So it is preferable if you have a single environment that you can create Linux and Windows binaries from rather than running 2 separate........
MySQL on Debian versions is configured differently than the native local MySQL plugin so you will be disappointed when your password on the mysql client fails by default.
Here is how you reset the MySQL root password the proper and "working way"
#first we gracefully stop mysql
sudo systemctl stop mysql;
#then we forcefully kill any mysqld process just in case
sudo killall -9 mysqld mysqld_safe;........
The reason for doing this is that the installer doesn't seem to work properly for LUKS and the server installer doesn't even support LUKS anymore. When you use the GUI install on Desktop for LUKS it won't boot and will just hang after you enter your password. So the only reliable way is to do it ourselves.
1.) Make a default minimal install of Ubuntu
2.) Have a secondary disk on the server or VM.
3.)........
The cool thing here is that we only need 1 drive to make a RAID 10 or RAID 1 array, we just tell the Linux mdadm utility that the other drive is "missing" and we can then add our original drive to the array after booting into our new RAID array.
Step#1 Install tools we need
yum -y install mdadm rsync
Step #2 Create your partitions on the drive that will be our RAID array
Here I assume it is /dev........
service sshd status
● ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
Active: failed (Result: start-limit-hit) since Wed 2019-10-02 11:07:54 EDT; 36s ago
Process: 476 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255)
Oct 02 11:07:54 box systemd[1]: Failed to start OpenBSD Secure Shell server.
Oct 02 11:07:54 box sys........
Install Errors on Version 12:
This error happened on QEMU emulator version 2.11.1 pve-qemu-kvm_2.11.1-5
on Proxmox/Debian but installing on QEMU.12 on Centos 6 did not produce the error.
*Update it is not related to the OS or QEMU version. This happened in Centos 6 too after a second install.
What really causes this even though you successfully install........
If you get error messages like this it is usually because /var/run/sshd does not exist.
root@userbox:/# service sshd status
● ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab
Active: failed (Result: start-limit-hit) since Wed 2019-04-10 02:24:44 EDT; 1
Process: 511 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255)........
For some reason, perhaps you don't want to run a daemon or let Letsencrypt have access to your production server.
There is a way to use it like a normal CSR/CA setup in manual mode.
./letsencrypt-auto certonly --manual -d realtechtalk.com - www.realtechtalk.com
Eventually you will get prompted to create a certain path and file with certain data:
Create a file containing just this data:
Casdfasfadsfsad........
The key thing is that you must use a "machine"id of "pc-1.3" or it will say your hardware is not supported.
Additionally you MUST use a virtio disk or you will get a ks_pre.sh error as soon as the install starts (a look at logs will show it can't find a disk). This is funny because even though the OS finds the disk and an fdisk -l shows it, it looks like the script looks for a /dev/vda device (virtio) and nothing else, so if you didn't use Virtio as you........
This is not about systemd/systemctl and not about "onboot" so there's no rc.local trick here but it's the GUI/Gnome etc when a user logs in that a command is launched.
Put this in your home dir
The .config/autostart directory is where Linux Mint/Ubuntu checks for autostart application config files
mkdir -p ~/.config/autostart
Create a new entry/file that starts an application........
In a RAID array I had a have periodically lost a drive here and there over the past several months. Iwas always able to readd and resync without losing data. However at some point it looks like some minor corruption happened and this makes DRBD unhappy.
Using fsck did not help either.
Dec 19 06:01:45 storageboxtest4 kernel: [19005.945890] EXT3-fs error (device drbd0): ext3_get_inode_loc: unable to read inode block - inode=22184379........
umask are the default permissions that are applied when a file or directory are created. To see this in action simply just "touch filename" or "mkdir somedir" and you'll see what default permissions are applied.
The first thing Ialways tell people you should know is to NEVER change the defaults unless you are making them more restrictive. But they work well and if you change the defaults you could end up creating a file without permission to read........
[root@localhost:~] vmkping -I vmk1 10.0.2.69
PING 10.0.2.69 (10.0.2.69): 56 data bytes
sendto() failed (Host is down)
vsphere distributed switch vmotion not working
[root@localhost:~] esxcfg-route -l
VMkernel Routes:
Network Netmask Gateway Interface&........
[root@localhost:~]
BootModuleConfig.sh echo host-ind nfcd........
Server Side Config
1.) First install nfs-utils
yum -y install nfs-utils
2.) Configure nfs share
Create a directory for your NFS share
mkdir /datastore
Create your NFS share in /etc/exports
echo "/datastore 10.220.101.0/24(rw,sync,no_root_squash)" >> /etc/exports
systemctl restart nfs........
sudo apt-get install nfs-kernel-server #oops there are no exports so it won't startsudo /etc/init.d/nfs-kernel-server start* Not starting NFS kernel daemon: no exports.
#we will use the /tmp/nfstestshare directory for our NFS share
mkdir /tmp/nfstestshare
#add it to /etc/exports (basically what NFS checks to determine what to make an NFS share)
/tmp/nfstestshare 192.168.1.5(rw,sync,........
It has been a big pain for a long-time to install Windows from a Linux environment. I used to run a windows install server and it never worked right for some reason (the install would fail on most servers).
Before getting start be sure to setup your samba share so once you boot into WinPE you can mount the install for whatever Windows you want
/etc/samba/smb.conf
[smbwinstall]
path = /tftpboot/images/winstall
guest ok = yes........
Centos 6 requires GLIBC 2.12 however a lot of new programs you would want to compile may need a newer glibc. You can't remove the old glibc since the whole OS is based on it but you can install the updated glibc alongside it and do an export pointing to your updated GLIBC.
mkdir ~/glibc_install; cd ~/glibc_install
wget http://ftp.gnu.org/gnu/glibc/glibc-2.14.tar.gz........
yum -y install samba
vi /etc/samba/smb.conf
https://www.kernel.org/pub/linux/utils/boot/syslinux/syslinux-6.03.zip
mkdir syslinux;cd syslinux;unzip syslinux-6.03.zip
mkdir -p /tftpboot/libs/
cp bios/com32/modules/linux.c32 /tftpboot/libs/
cp bios/com32/libutil/libutil.c32 /tftpboot/libs/
cp bios/com32/lib/libcom32.c32 /tftpboot/libs/
#add lib path
echo "PATH libs" >> /tftpboot/pxeli........
A great way if you have a bunch of drives and mdadm connected and are looking for backups/archives and don't know what is where!
for md in `cat /proc/mdstat|grep md[0-99]|awk '{print $1}'`; do mkdir /mnt/$md; mount /dev/$md /mnt/$md; done........
#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 ........
Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler! Hint do not use grub2-install!
If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide.
One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting
The nor........
sudo mkdir -p /etc/X11/xorg.conf.d/
sudo vi /etc/X11/xorg.conf.d/20-intel.conf
On newer Ubuntu / Mint / Debian systems the file would go in: /usr/share/X11/xorg.conf.d/20-intel.conf
Type "i" and enter the following:
Section "Device"
Identifier "Intel Graphics"
Driver&n........
*Update so this doesn't work it must be something to do with the path of nfs or something else but the installer fails with "Installer crashed" at the end whereas with the CD/USB it works.
This assumes you've already installed and configured a separate PXE/DHCP server somewhere else and your /tftpboot directory is setup.
This is for Linux Mint 18.1 but generally applies to most versions although you may have tro change things like "casper"........
Just make sure you have php-xdebug installed and edit your php.ini:
[xdebug]
xdebug.profiler_enable = 0
xdebug.profiler_enable_trigger = 1
xdebug.profiler_output_dir = "/tmp/xdebug/"
xdebug.output_name = "cachegrind.out.%t-%s"
Also make and set permissions on /tmp/xdebug:
mkdir /tmp/xdebug
chmod 777 /tmp/xdeb........
Based on this tutorial: http://www.linuxjournal.com/content/overlay-images-video-using-mplayer-and-mencoder
mencoder -oac pcm -ovc raw -vf bmovl=0:0:tfifo -o $output $file
vf_bmovl: Unknown command: ''. Ignoring. ........
1.) Replicate the number of partitions in your new drives.
gdisk /dev/sda
gdisk /dev/sdb
I created 3 partitions of the same same size.
partition #1: +1G (/boot)
partition #2: +60G (swap)
partition #3: rest of it (/)
#note if you are using GPT/gdisk you need to create separate a partition at least 1MB in size (in my case I would a 4th partition and mark it type ef02).........
This actually only happened after an e-mail server ran out of space due to run away log files. Normal Desktop clients were not affected. It appeared to be a bug in K9 mail but even reinstalling/wiping all settings did not fix it (read e-mails would still not reappear).
This is moreso a bug in Dovecot where it probably messes up the index files.
How do you fix this in Dovecot/your e-mail server?
You need to delete the do........
It is already known this is not possible
mdadm --create /dev/md3 --level 10 --layout=f2 --raid-devices=2 /dev/sdc1 /dev/sdd1
mdadm: /dev/sdc1 appears to be part of a raid array:
level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016
mdadm: /dev/sdd1 appears to be part of a raid array:
level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016
Continue creating ar........
It all comes down to a bug essentially where you are running an older kernel that doesn't support the newer Debian templates. The solution is to update your OpenVZ kernel.
Here are some symptoms of the problem/lack of kernel support:
Ubuntu Template 12.04 requires a manual network start:
service networking start
sshd will not start:
/usr/sbin/sshd
PRNG is not seeded
mknod /dev/random c 1 8........
Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access.
So in this case you add a second physical or disk or already ha........
sudo apt-get install zoneminder
[sudo] password for one:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
libuser-perl python-evince kdebase-apps kwrite unixodbc
libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp
python-mediaprof........
Linux box13. 2.6.32-042stab076.5 #1 SMP Mon Mar 18 20:41:34 MSK 2013 x86_64 x86_64 x86_64 GNU/Linux
even setting privvmpages to a specific setting DOES not affect "free -m" in containers.
This is probably a kernel issue
23:36:29 up 159 days, 7:12, 4 users, load average: 0.42, 0.44, 0.33
[root@box13 ~]# free -m
total&n........
/scripts/phpextensionmgr install PHPSuHosin
Updating md5sum list
Fetching http://httpupdate.cpanel.net/cpanelsync/easy/targz.yaml (connected:0).......(request attempt 1/12)...Resolving httpupdate.cpanel.net...(resolve attempt 1/65)...
Fetching http://httpupdate.cpanel.net/mirror_addr_list (connected:0).......(request attempt 1/3)......connecting to 74.50.120.123...@74.50.120.123......connected......receiving...100%......request success......Done........
mkdir: cannot create directory 'test': Disk quota exceeded
You are out of inodes usually:
df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/simfs 200000 200000 0 100% /
none ........
The error itself "mkdir(): Too Many Links" is not very useful, but I'll translate it into plain English.
It means you've reached the filesystem's limit of how many directories can be created in a single directory.
In this case for ext3 the limit is 32000 and it was exceeded.
What's the solution?
The simple solution is to move those directories into more subdirectories possibly sorting them by date, alphabet or numerically.........
This is useful for developing a lot of applications, I'm putting it here to keep it handy for myself and hopefully others:
Choose CountryCanadaJapanUnited StatesUnited KingdomAfghanistan........
There are 3 pieces that are required to restore and make it work (of course consider if any kernel modules need to re-enabled and if you need to change the IPs):
Copy the vz/private/VEID directory to /vz/private
Copy the /etc/vz/conf/VEID.conf to /etc/vz/conf/
mkdir /vz/root/VEID
After that you should be able to see the VE in vzlist -a
You should then be able to start it normally.........
This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel.
I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk.
I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one).
This is strange but it seems like this Xen PV guest has some sort of hidden or........
This is something I often setup for clients because it's very helpful for people in datacenters, this allows custom OS installs on demand, you can customize it more by using kickstart etc.. but here's a base I use before customizing more:
This little script below will install everything you need to get booting by PXE Linux.
It also assumes you set a local IP (be sure not to overwrite your existing IP) on eth0:0 (note the :0) as 192.168.1.10 and it........
I had a system running a 128MB live CD image with 2.8 gigs of available RAM and the OOM kernel killer went crazy when using dd for more than 8 minutes and kept killing everything. I've read that this is due to a low-memory issue and paging in the kernel and 32-bit systems with lots of RAM.
I even enabled swapspace on my LiveCD and the issue happened 25 minutes into dd rather than 8 minutes, so what gives?
Also no swap space was ever used!
cat /proc/s........
drup 6.2 install
$cd drupgoodinst3883/
[ drupgoodinst3883]$ ls
CHANGELOG.txt cron.php index.php INSTALL.pgsql.txt INSTALL.txt MAINTAINERS.txt modules robots.txt sites update.php xmlrpc.php
COPYRIGHT.txt includes INSTALL.mysql.txt install.php LICENSE.txt misc&........
Make sure the module "tun" is loaded on the host.
vzctl set 2000 --devnodes net/tun:rw --save
*Note what's below is what OpenVZ says you need (but I've never had to do it)
vzctl exec 2000 mkdir -p /dev/net
vzctl exec 2000 mknod /dev/net/tun c 10 200
vzctl exec 2000 chmod 600 /dev/net/tun
On the container test the device:
when Something is wrong:........
Dovecot enable SSL (by default it uses an old expired cert if you choose pop3s and imaps as protocols)
===================
Create Cert & Key:
openssl req -new -x509 -nodes -days 1530 -out server.crt -keyout server.key
mkdir /etc/mailssl
chmod 700 /etc/mailssl
cp server.* /etc/mailssl
Edit /etc/dovecot.conf
ssl_cert_file = /etc/mailssl/server.crt
s........
Create Cert & Key:
openssl req -new -x509 -nodes -days 1530 -out server.crt -keyout server.key
mkdir /etc/mailssl
chmod 700 /etc/mailssl
cp server.* /etc/mailssl
Postfix SSL config
Edit /etc/postfix/main.cf:
#SSL stuff
smtpd_tls_cert_file = /etc/mailssl/server.crt
smtpd_tls_key_file = /etc/mailssl/server.key
To make smtps w........
Webmin Setup Centos 5:
wget http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html&ts=1294339690&use_mirror=surfnet
[1] 24229
[2] 24230
[root@host ~]# --2011-01-06 21:48:20-- http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html
Resolving downloads.sourceforge.net... 216.34.181.........
Copy the initrd to somewhere else, say /tmp:
mv initrd.img to initrd.gz
*the mv to .gz is needed otherwise gunzip won't work/it will refuse to operate without the correct .gz extension
gunzip initrd.gz
cat initrd | cpio -idmv
The last command extracts the contents of initrd to your present working directory.
For 7z .lz initrd........
yum exits in the middle
The problem is this VPS seems to be an OpenVZ template from HyperVM. The only way to make it work was to disable i386 packages since this was an x64 kernel. That shouldn't be necessary but it was the only way to make yum stop quitting after the first package or two. I couldn't find any issue by checking the logs either.
echo y|yum install vim-minimal telnet expect jwhois net-tools slocate iptables elinks gawk
L........
This was done on Centos butI think it's easier on Debian machines, the paths that it is set to use are tailored towards Debian, so there is some fiddling that needs to be done on Centos.
This is for chrooting ssh, but jailkit has other uses than just SSH jails but I won't cover them in this writeup.
1. Install jailkit
yum install jailkit
2. Setup Jail Home
mkdir /home/jail
chown root:root /home/ja........
This is based on Debian Linux but should apply equally to any *nix distro.
Install LUKS/crypt-setup
apt-get install cryptsetup
Setup your LUKS Partition
Of course change /dev/md2 with whatever partition you intend to use LUKS on.
cryptsetup --verbose --verify-passphrase luksFormat /dev/md2
You'll be asked to verify your decryption password twice
*DO NOT FORGET THIS PASSWORD AS IT IS NOT RECOVERABLE!........
I installed 5.5 with a 300GB RAID 1 partition (boot is also on this partition). It booted up fine the first few times until after I used a Live CD and accessed the array, and it became named /dev/md127 for some reason.
Now whenI boot into CentOS I get a kernel panic and different errors, once I got "invalid superblock", even though the array is fine (it didn't happen again, probably because I was sure to dismount and stop the mdadm array properly).
Here's what........
This is a very simple solution, but most guides out there make you login twice (once to scp the key) and once to put the key in authorized_keys. There's no need for that.
If you don't already have a ~/.ssh/id_rsa.pub just type "ssh-keygen -t rsa" and keep hitting enter until it's done :)
Just use this code to easily enable passwordless login with SSHD
key=`cat ~/.ssh/id_rsa.pub`;ssh user@192.168.5.25 "echo $key >> ~/.ssh/auth........
Out of memory: kill process 7559 (rsync) score 635 or a child
Killed process 7559 (rsync)
I was surprised to see this in my dmesg whenmy rsync backup suddenly stalled/stopped.
This system has 3 gigs of RAM and lots of free memory so I don't understand what is happening.
rsync invoked oom-killer: gfp_mask=0x200d2, order=0, oomkilladj=0
Pid: 7600, comm: rsync Not tainted 2.6.24.2 #83
[] oom_kill_pr........
Before we start I take no responsibility for this, you should have a backup and if you make a mistake during this process you could wipe out all of your data. So backup somewhere else before starting this as a precaution, or make sure it's data you could afford to lose.
The RAID 1 Setup (Hardware Wise)
I've already setup my 2 x 1TB (Seagate) drives with identical partitions, make sure your new hard drive (the empty one) is setup like your curr........
I have no idea why but mkfs.ext3 defaults to a patheticlly small blocksize of 1024 bytes/1KB (kilobyte). That means the maximum filesize is ONLY 16GB! With 2KB/2048 bytes you get a 256 GB maximum filesize, and with 4KB/4096 bytes you get 2TB!
I finally noticed/paid attention to this after realizing that with rsync and scp that no file larger than 17GB could be transferred. I then realized it must be a file size limit on the partition.
Here is what tune2fs tol........
PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist:
[code:1:1fd0f3abbe]
if (!file_exists($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........
How to extract files from RPM & SRPM filesmkdir any_directory
cd any_directory
rpm2cpio /location/of/package.src.rpm | cpio -d -i
This will extract all files, I find it especially useful if you want to manually compile the kernel source from the srpm........
For some reason Ikeep getting this error when trying to run a sudo command eg:
sudo -u someuser somecommand
sudo: Error dropping capabilities, aborting
My version of sudo is:sudo-1.6.9p17-3.el5_3.1 and I've heard that version 1.7 fixes everything. The only thing is yum does not think sudo has any update. Iguess the new version has not been committed to the RPM repository yet.
This is really a huge and ann........
To enable Fuse to work inside a OpenVZ container it's very simple (although some people say it can't be done).
Remember that on your HN(HostNode) for OpenVZ, Fuse must be installed and the module must be loaded for this to work. In addition remember that you need the Fuse package installed inside the container of course.
vzctl set 2000 --devices c:10:229:rw --save
vzctl exec 2000 mknod /dev/fuse c 10 229
The part that most people forget........
genisoimage: Directories too deep for 'Backup/My Documents/My Music/iTunes/Album Artwork/Local/5928CE9C1AFAC465/07/15' (7) max is 6.
Some people said choosing the --iso-level-4 option will help. I just opted to add the "-D" switch and everything was fine.........
There's a lot of information and guides on OCFS2 for RHELand Centos Linux but the package setup and configuration is slightly different and this has thrown some people off.
Installing OC2FS
You should install the following packages to get started:
apt-get install ocfs2-tools ocfs2console
Configure OC2FS
In RHEL/Centos the main configuration file is located in /etc/sysconfig/o2cb
However in Debian based Linux it is located........
There's a lot of outdated information and confusion for system administrator's out there.
One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle.
At a later date we'll cover how scripting can automatically backup certain........