The technology blog that consist of technology updates, How-to Setup, Troubleshoot Problem, Fix Errors on Linux Server
It is best practice to remember passwords, but because too many passwords, sometimes we forget.
We are not encouraged to write the password on any paper or share the password via email. This can lead to more serious security issues. Continue reading “How to Reset the Directory Manager Password on RHEL 7 / CentOS 7”
This article will explain the steps to reset a lost root password or to reset forgotten root password on Linux RHEL 7 or CentOS 7.
Basically, the steps will adding a “rd.break” to the end of the line with kernel parameters in Grub to stops the start up process before the regular root filesystem is mounted, hence the necessity to chroot into sysroot. Continue reading “How to Reset Forgotten Root Password on Linux RHEL 7/CentOS 7”
This article will explain and share how to add and remove user account with useradd(add) and userdel (remove) from the command-line on linux RHEL 6/7, CentOS 6/7, Oracle Linux 6/7 server.
1. Adding a New User to an Linux System.
a) Get the useradd manual :
# man useradd
useradd - create a new user or update default new user information
b) To creates the new account and the /home/john home directory :
# useradd --home /home/ehowstuff ehowstuff
c) useraddd command does not set any valid password by default, and user cannot log in until a password is set.To set the password user the following command :
# passwd ehowstuff Changing password for user ehowstuff. New password: Retype new password: passwd: all authentication tokens updated successfully.
d) Verify the values in /etc/password :
# cat /etc/passwd | grep ehowstuff ehowstuff:x:501:501::/home/ehowstuff:/bin/bash
e) Verify the values in /etc/group :
# cat /etc/group | grep ehowstuff ehowstuff:x:501:
f) Verify email user created for id ehowstuff :
# ls /var/spool/mail | grep ehowstuff ehowstuff
More useradd options :
-c, –comment COMMENT
Add a value, such as a full name, to the GECOS field.
-g, –gid GROUP
Specify the primary group for the user account.
-G, –groups GROUPS
Specify a list if supplementary groups for the user account.
-a, –append
Used with the -G option to append the user to the supplemental groups mentioned without removing the user from other groups.
-d, –home HOME_DIR
Specify a new home directory to a new location. Must be used with the -d option.
-m, –move-home
Move a user home directory to a new location. Must be used with the -d option.
-s, –shell SHELL
Specify a new login shell for the user account.
-L, –lock
Lock a user account.
-U, –unlock
Unlock a user account.
2. Deleting a User from an Linux System.
a) Get userdel manual :
# man userdel
userdel - delete a user account and related files
b) userdel username removes the user from /etc/passwd, but leaves the home directory intact by default. Proper command to remove the user’s account, user’s home directory and mail spool as part of the deletion process :
# userdel --remove ehowstuff
or
# userdel -r ehowstuff
Warning :
When a user is removed with userdel without the -r option specified, the system will have files that are owned by an unassigned user ID number. This can also happen when files created by a deleted user exist outside their home directory. This situation can lead to information leakage and other security issues.
Old method to change the runlevel via /etc/inittab in Redhat Enterprise Linux version and CentOS server has become obsolete on RHEL 7 and CentOS 7. This latest Linux operating system uses systemd system management daemon and relies on systemctl command in order to change the runlevel. RunLevel is set with linking to /etc/systemd/system/default.target. Please make sure you have already install Gnome GUI before you proceed to change runlevel.
1. Check the current runlevel :
# runlevel N 3
or
# systemctl get-default multi-user.target
2. We can display the default.target by using list command :
# ll /etc/systemd/system/default.target lrwxrwxrwx. 1 root root 37 Sep 1 2014 /etc/systemd/system/default.target -> /lib/systemd/system/multi-user.target
3. For example to list all currently loaded targets :
# systemctl list-units -t target
UNIT LOAD ACTIVE SUB DESCRIPTION basic.target loaded active active Basic System cryptsetup.target loaded active active Encrypted Volumes getty.target loaded active active Login Prompts local-fs-pre.target loaded active active Local File Systems (Pre) local-fs.target loaded active active Local File Systems multi-user.target loaded active active Multi-User System network.target loaded active active Network paths.target loaded active active Paths remote-fs.target loaded active active Remote File Systems slices.target loaded active active Slices sockets.target loaded active active Sockets swap.target loaded active active Swap sysinit.target loaded active active System Initialization timers.target loaded active active Timers LOAD = Reflects whether the unit definition was properly loaded. ACTIVE = The high-level unit activation state, i.e. generalization of SUB. SUB = The low-level unit activation state, values depend on unit type. 14 loaded units listed. Pass --all to see loaded but inactive units, too. To show all installed unit files use 'systemctl list-unit-files'.
4. Type the following command to change the RunLevel to Graphical-login :
# systemctl set-default graphical.target
rm '/etc/systemd/system/default.target' ln -s '/usr/lib/systemd/system/graphical.target' '/etc/systemd/system/default.target'
5. Verify the changed runlevel :
# runlevel N 5
or
# systemctl get-default graphical.target
6. Reboot the server to login to GNOME gui.
Epel yum repository is an open source centos yum repository or rpm repository for developers and system administrators to perform the installation of RPM packages via yum on their virtual private server (VPS) or dedicated server.
EPEL yum repository is redhat yum repository for CentOS and additional yum repository for the existing CentOS repository.
It provides 100 % high quality software packages for Linux distributions, including RHEL (Red Hat Enterprise Linux), CentOS and Debian, and all packages maintained by Fedora repo team.
1. Prepare EPEL repository for RHEL 7/CentOS 7 64 bit (epel centos 7/epel rhel 7) :
# sudo rpm --import https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-7 # # sudo rpm -Uvh https://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-9.noarch.rpm
Example :
# sudo rpm --import https://dl.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-7 # sudo rpm -Uvh https://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-9.noarch.rpm Retrieving https://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-9.noarch.rpm Preparing... ################################# [100%] Updating / installing... 1:epel-release-7-9 ################################# [100%]
In CentOS 7, an alternative way to install the EPEL repo is by using the command yum :
# sudo yum install epel-release -y
2. Command to verify that the EPEL repository is enabled.
# sudo yum repolist
Sample output :
# sudo yum repolist Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.linode.com * epel: ftp.osuosl.org * extras: mirrors.linode.com * updates: mirrors.linode.com repo id repo name status base/7/x86_64 CentOS-7 - Base 9,363 epel/x86_64 Extra Packages for Enterprise Linux 7 - x86_64 11,046 extras/7/x86_64 CentOS-7 - Extras 200 nginx/x86_64 nginx repo 41 updates/7/x86_64 CentOS-7 - Updates 438 varnish-4.1/x86_64 Varnish Cache 4.1 for Enterprise Linux 31 repolist: 21,119
3. Install httpd package using epel repo option –enablerepo=epel :
# sudo yum --enablerepo=epel install httpd
Nginx web server is alternative web server to Apache and Lighttpd. Nginx popularity now growing because it focuses on high concurrency, high performance while maintaining low memory usage. However, due to certain reasons webmaster or system administrator can not use Nginx on their server and decide to uninstall Nginx. Most of the webmaster, administrator and programmer still prefer to user Apache over Nginx as a web server because of the following reasons :
For the linux server platform that running on CentOS 7, RHEL 7 and Oracle linux 7, the removal step for Nginx is quite different from older version. Therefore, this article will explain the steps to remove or uninstall Nginx that was installed from source on CentOS 7, RHEL 7 and Oracle Linux 7.
1. Stop Nginx service and remove Nginx auto start script :
[root@rhel7 ~]# sudo systemctl stop nginx.service [root@rhel7 ~]# sudo systemctl disable nginx.service
2. Remove Nginx user and it related directory :
[root@rhel7 ~]# sudo userdel -r nginx
3. Delete and related Nginx installation directory :
[root@rhel7 ~]# sudo rm -rf /etc/nginx [root@rhel7 ~]# sudo rm -rf /var/log/nginx [root@rhel7 ~]# sudo rm -rf /var/cache/nginx/
4. Remove the created nginx.service script under systemd :
[root@rhel7 ~]# sudo rm -rf /usr/lib/systemd/system/nginx.service
One recommended way to manage virtual private server (VPS) or a dedicated linux server is not using the root account as the main access for SSH login. This is because usually the hackers will try to brute force your root password and potentially get access to your server. Instead of using the default root account, you can create a new account and assign root privileges to it and issue the sudo command line to root from it. Please make sure that the normal user account given root privileges accounts work properly before you disable the default root login access. The following command has been tested works on CentOS 6, CentOS 7, RHEL 6 and RHEL 7 VPS.
[root@vps ~]# useradd skytech [root@vps ~]# passwd skytech Changing password for user skytech. New password: Retype new password: passwd: all authentication tokens updated successfully.
[root@vps ~]# visudo
Add the following code at the bottom of the file and save the file with the command :wq :
## Allow skytech user to run any commands anywhere skytech ALL=(ALL) ALL
This will grant a root privileges to the normal user skytech.
Storage technology plays a important role in improving the availability, performance, and ability to manage Linux servers.
One of the most useful and helpful technology to linux system administrator is Linux Logical Volume Manager(LVM), version 2 (or LVM 2).
LVM is a widely-used technique and extremely flexible disk management scheme for deploying logical rather than physical storage. With LVM, system administrator can easily resize and extend the logical drive when it is required.
The following steps will describe how to create LVM in Linux CentOS 7 or RHEL 7 or Oracle Linux 7.
1. Add the new 20GB vdisk from the ESXi or vCenter :
2. create a new Partiton using fdisk tool and select partition type LVM :
[root@centos7 ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xfd3bf27d.
Command (m for help): n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-41943039, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039):
Using default value 41943039
Partition 1 of type Linux and of size 20 GiB is set
Command (m for help): p
Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xfd3bf27d
Device Boot Start End Blocks Id System
/dev/sdb1 2048 41943039 20970496 83 Linux
Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): L
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 39 Plan 9 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 3c PartitionMagic 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 40 Venix 80286 85 Linux extended c7 Syrinx
5 Extended 41 PPC PReP Boot 86 NTFS volume set da Non-FS data
6 FAT16 42 SFS 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS/exFAT 4d QNX4.x 88 Linux plaintext de Dell Utility
8 AIX 4e QNX4.x 2nd part 8e Linux LVM df BootIt
9 AIX bootable 4f QNX4.x 3rd part 93 Amoeba e1 DOS access
a OS/2 Boot Manag 50 OnTrack DM 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 51 OnTrack DM6 Aux 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 52 CP/M a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD ee GPT
f W95 Ext'd (LBA) 54 OnTrackDM6 a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 55 EZ-Drive a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 56 Golden Bow a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 5c Priam Edisk a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 61 SpeedStor ab Darwin boot f2 DOS secondary
16 Hidden FAT16 63 GNU HURD or Sys af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 65 Novell Netware b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 75 PC/IX be Solaris boot ff BBT
1e Hidden W95 FAT1 80 Old Minix
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): p
Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xfd3bf27d
Device Boot Start End Blocks Id System
/dev/sdb1 2048 41943039 20970496 8e Linux LVM
3. Initializes the partition /dev/sdb1 as an LVM physical volume :
[root@centos7 ~]# pvcreate /dev/sdb1 Physical volume "/dev/sdb1" successfully created
4. Scanning for Block Devices
[root@centos7 ~]# lvmdiskscan /dev/centos/swap [ 2.00 GiB] /dev/sda1 [ 500.00 MiB] /dev/centos/root [ 27.51 GiB] /dev/sda2 [ 29.51 GiB] LVM physical volume /dev/sdb1 [ 20.00 GiB] LVM physical volume 2 disks 1 partition 0 LVM physical volume whole disks 2 LVM physical volumes
5. Displaying Physical Volumes :
There are three commands you can use to display properties of LVM physical volumes: pvs,
pvdisplay, and pvscan.
The pvdisplay command provides a verbose multi-line output for each physical volume. It displays
physical properties (size, extents, volume group, etc.) in a fixed format.
[root@centos7 ~]# pvdisplay --- Physical volume --- PV Name /dev/sda2 VG Name centos PV Size 29.51 GiB / not usable 3.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 7554 Free PE 0 Allocated PE 7554 PV UUID JvDOto-KDiF-gtca-TveX-ne9M-frsB-qsP1aJ "/dev/sdb1" is a new physical volume of "20.00 GiB" --- NEW Physical volume --- PV Name /dev/sdb1 VG Name PV Size 20.00 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID rJ8wl7-xzIN-2qqV-ov7Z-lHKe-ELge-aAV29V
The pvscan command scans all supported LVM block devices in the system for physical volumes
[root@centos7 ~]# pvscan PV /dev/sda2 VG centos lvm2 [29.51 GiB / 0 free] PV /dev/sdb1 lvm2 [20.00 GiB] Total: 2 [49.51 GiB] / in use: 1 [29.51 GiB] / in no VG: 1 [20.00 GiB]
6. Create volume group name vg_newlvm and add /dev/sdb1 partition into the group.
[root@centos7 ~]# vgcreate vg_newlvm /dev/sdb1 Volume group "vg_newlvm" successfully created
If you have more than one partition, you can add multiple partition in single command. This command creates a local volume named vg_newlvm that contains physical volumes /dev/sdb1 and /dev/sdc1 :
[root@centos7 ~]# vgcreate vg_newlvm /dev/sdb1 /dev/sdc1
7. Creates a logical volume called centos7_newvol that uses all of the unallocated space in the volume group vg_newlvm :
[root@centos7 ~]# lvcreate --name centos7_newvol -l 100%FREE vg_newlvm Logical volume "centos7_newvol" created
You can see more example of lvcreate command in article “4 lvcreate Command Examples on Linux”
8. Display the created logical volumes :
[root@centos7 ~]# lvdisplay
.. .. --- Logical volume --- LV Path /dev/vg_newlvm/centos7_newvol LV Name centos7_newvol VG Name vg_newlvm LV UUID szlkNP-0lwe-f59Z-PJVU-X7pG-unBL-qN10D4 LV Write Access read/write LV Creation host, time centos7.ehowstuff.local, 2015-01-25 15:15:48 +0800 LV Status available # open 0 LV Size 20.00 GiB Current LE 5119 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:2
9. Use the mkfs command to format a newly created LVM :
[root@centos7 ~]# mkfs.ext4 /dev/vg_newlvm/centos7_newvol
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
1310720 inodes, 5241856 blocks
262092 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2153775104
160 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
10. Create the mount point and mount the new LVM :
[root@centos7 ~]# mkdir -p /data [root@centos7 ~]# mount /dev/vg_newlvm/centos7_newvol /data
11. Verify thew new disk layout :
[root@centos7 ~]# df Filesystem 1K-blocks Used Available Use% Mounted on /dev/mapper/centos-root 28260132 9191032 17610516 35% / devtmpfs 1935888 0 1935888 0% /dev tmpfs 1941892 0 1941892 0% /dev/shm tmpfs 1941892 8728 1933164 1% /run tmpfs 1941892 0 1941892 0% /sys/fs/cgroup /dev/sda1 487634 73191 384747 16% /boot tmpfs 1941892 8728 1933164 1% /var/named/chroot/run/named /dev/mapper/vg_newlvm-centos7_newvol 20507216 45080 19397384 1% /data
When you need to add a hard disk or network interface cards on the new VMware virtual machine on the production server, but you are not allowed to shutdown the server or you have several related issues as below. The following quick article shows how to rescan SCSI Bus to add or remove a SCSI Devices on Linux.
This steps may work on CentOS 5/6/7 and RHEL 5/6/7.
After Red Hat Enterprise Linux 5.0 (RHEL 5) and above (RHEL 6 and RHEL 7), it is possible to make changes to the SCSI I/O subsystem without rebooting.
1. Identify host bus number :
# ls /sys/class/scsi_host/ host0 host1 host2
2. Rescan the SCSI Bus to Add a SCSI Devices :
# echo "- - -" > /sys/class/scsi_host/host0/scan # echo "- - -" > /sys/class/scsi_host/host1/scan # echo "- - -" > /sys/class/scsi_host/host2/scan
Reference :
Normally when you have added new storage to a running Virtual machine, you probably won’t see the new storage automatically.
This is because the SCSI bus to which the storage devices are connected needs to be rescanned to make the new hardware visible.
As a system administrator, to maintain the linux server uptime is very important and it is better to add a new hard disk without reboot the server.
There is one simple command to rescan the SCSI Bus and add SCSI Devices. The command will trigger the linux rescan scsi bus device on the system.
The following steps has been tested on CentOS 7, RHEL 7 and Oracle Linux 7.
1. Add the new 20GB vdisk from the ESXi or vCenter :
2. Show current disk and partition :
[root@centos7 ~]# fdisk -l
Disk /dev/sda: 32.2 GB, 32212254720 bytes, 62914560 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x0006b96a Device Boot Start End Blocks Id System /dev/sda1 * 2048 1026047 512000 83 Linux /dev/sda2 1026048 62914559 30944256 8e Linux LVM Disk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk /dev/mapper/centos-root: 29.5 GB, 29536288768 bytes, 57688064 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes
3. Identify host bus number :
[root@centos7 ~]# ls /sys/class/scsi_host/ host0 host1 host2
4. Rescan the SCSI Bus to Add a SCSI Devices :
[root@centos7 ~]# echo "- - -" > /sys/class/scsi_host/host0/scan [root@centos7 ~]# echo "- - -" > /sys/class/scsi_host/host1/scan [root@centos7 ~]# echo "- - -" > /sys/class/scsi_host/host2/scan
4. Verify the disk and partiton and make sure 20GB has been added. In this case, the following line appeared “Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors” and confirmed that 20GB has been added without reboot the server :
[root@centos7 ~]# fdisk -l Disk /dev/sda: 32.2 GB, 32212254720 bytes, 62914560 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x0006b96a Device Boot Start End Blocks Id System /dev/sda1 * 2048 1026047 512000 83 Linux /dev/sda2 1026048 62914559 30944256 8e Linux LVM Disk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk /dev/mapper/centos-root: 29.5 GB, 29536288768 bytes, 57688064 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes
Before we install Zimbra 8, I would recommend you to meet all of these requirements. Some software prerequisites should be installed first, then setup the DNS and MX records, provides internet access to and from the Zimbra server, install the latest patches on the server zimbra 8, properly configure iptables filter or firewalld service, turn off SELinux, turn off unnecessary services that can interfere with the process installation. As a guide, i have prepared a checklist or step -by-step reference to Zimbra e-mail administrator. These steps have been tested on RHEL 7/CentOS 7
1. Prepare for a fully qualified domain name ( FQDN ) for your Zimbra mail server mx record and ensure your domain is configured correctly.
2. Configure /etc/hosts and hostname.
3. Allow iptables to by-pass all zimbra ports.
4. Disabled SELINUX :
[root@centos7 ~]# vim /etc/sysconfig/selinux
Change enforcing to disabled :
# This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: # enforcing - SELinux security policy is enforced. # permissive - SELinux prints warnings instead of enforcing. # disabled - No SELinux policy is loaded. SELINUX=disabled # SELINUXTYPE= can take one of these two values: # targeted - Targeted processes are protected, # minimum - Modification of targeted policy. Only selected processes are protected. # mls - Multi Level Security protection. SELINUXTYPE=targeted
5. Stop sendmail, postfix or any MTA service :
[root@centos7 ~]# systemctl stop postfix [root@centos7 ~]# systemctl disable postfix [root@centos7 ~]# systemctl stop sendmail [root@centos7 ~]# systemctl disable sendmail
6. Make sure CentOS and RHEL is the latest :
[root@centos7 ~]# yum update -y
7. Install the required packages and libraries using the following command :
[root@centos7 ~]# yum install perl perl-core ntpl nmap sudo libidn gmp libaio libstdc++ unzip sysstat sqlite -y
Zimbra 8.6.0 brings new features, improvements in Mail server and better web clients experience. Some that caught my attention was local lmtp client can communicate over ssl for mail server, better organization of shared folders for web client and the calendar now can run search on description for location or resources. You can get detailed information on this Release Notes. In this article, I will explain step by step how to install Zimbra 8.6.0 on RHEL 7 or CentOS 7. Starting with ZCS8.5 and later, there is now a DNS caching service available for installation. However, i have excluded zimbra-dnscache in the installation steps.
Prepare for Zimbra 8 Installation Prerequisites on RHEL 7/CentOS 7
1. Log in as root to the server and download Zimbra Zimbra Open Source Edition 8.6.0 using the command wget. Before that, please make sure your Zimbra server can access the internet :
wget https://files.zimbra.com/downloads/8.6.0_GA/zcs-8.6.0_GA_1153.RHEL7_64.20141215151110.tgz
2. Extract the downloaded tar file :
tar xzf zcs-8.6.0_GA_1153.RHEL7_64.20141215151110.tgz
3. cd to the directory where the extracted ZCS Open Source Edition :
cd zcs-8.6.0_GA_1153.RHEL7_64.20141215151110
4. Start the installation with the following command :
./install.sh --platform-override
Full installation steps :
./install.sh --platform-override
Operations logged to /tmp/install.log.14668
Checking for existing installation...
zimbra-ldap...NOT FOUND
zimbra-logger...NOT FOUND
zimbra-mta...NOT FOUND
zimbra-dnscache...NOT FOUND
zimbra-snmp...NOT FOUND
zimbra-store...NOT FOUND
zimbra-apache...NOT FOUND
zimbra-spell...NOT FOUND
zimbra-convertd...NOT FOUND
zimbra-memcached...NOT FOUND
zimbra-proxy...NOT FOUND
zimbra-archiving...NOT FOUND
zimbra-core...NOT FOUND
PLEASE READ THIS AGREEMENT CAREFULLY BEFORE USING THE SOFTWARE.
ZIMBRA, INC. ("ZIMBRA") WILL ONLY LICENSE THIS SOFTWARE TO YOU IF YOU
FIRST ACCEPT THE TERMS OF THIS AGREEMENT. BY DOWNLOADING OR INSTALLING
THE SOFTWARE, OR USING THE PRODUCT, YOU ARE CONSENTING TO BE BOUND BY
THIS AGREEMENT. IF YOU DO NOT AGREE TO ALL OF THE TERMS OF THIS
AGREEMENT, THEN DO NOT DOWNLOAD, INSTALL OR USE THE PRODUCT.
License Terms for the Zimbra Collaboration Suite:
http://www.zimbra.com/license/zimbra-public-eula-2-5.html
Do you agree with the terms of the software license agreement? [N] y
Checking for prerequisites...
FOUND: NPTL
FOUND: nmap-ncat-6.40-4
FOUND: sudo-1.8.6p7-11
FOUND: libidn-1.28-3
FOUND: gmp-5.1.1-5
FOUND: libaio-0.3.109-12
FOUND: libstdc++-4.8.2-16.2
FOUND: unzip-6.0-13
FOUND: perl-core-5.16.3-283
Checking for suggested prerequisites...
FOUND: perl-5.16.3
FOUND: sysstat
FOUND: sqlite
Prerequisite check complete.
Checking for installable packages
Found zimbra-core
Found zimbra-ldap
Found zimbra-logger
Found zimbra-mta
Found zimbra-dnscache
Found zimbra-snmp
Found zimbra-store
Found zimbra-apache
Found zimbra-spell
Found zimbra-memcached
Found zimbra-proxy
Select the packages to install
Install zimbra-ldap [Y]
Install zimbra-logger [Y]
Install zimbra-mta [Y]
Install zimbra-dnscache [Y] N
Install zimbra-snmp [Y]
Install zimbra-store [Y]
Install zimbra-apache [Y]
Install zimbra-spell [Y]
Install zimbra-memcached [Y]
Install zimbra-proxy [Y]
Checking required space for zimbra-core
Checking space for zimbra-store
Checking required packages for zimbra-store
zimbra-store package check complete.
Installing:
zimbra-core
zimbra-ldap
zimbra-logger
zimbra-mta
zimbra-snmp
zimbra-store
zimbra-apache
zimbra-spell
zimbra-memcached
zimbra-proxy
The system will be modified. Continue? [N] Y
Removing /opt/zimbra
Removing zimbra crontab entry...done.
Cleaning up zimbra init scripts...done.
Cleaning up /etc/ld.so.conf...done.
Cleaning up /etc/security/limits.conf...done.
Finished removing Zimbra Collaboration Server.
Installing packages
zimbra-core......zimbra-core-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-ldap......zimbra-ldap-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-logger......zimbra-logger-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-mta......zimbra-mta-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-snmp......zimbra-snmp-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-store......zimbra-store-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-apache......zimbra-apache-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-spell......zimbra-spell-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-memcached......zimbra-memcached-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
zimbra-proxy......zimbra-proxy-8.6.0_GA_1153.RHEL7_64-20141215151110.x86_64.rpm...done
Operations logged to /tmp/zmsetup01032015-084819.log
Installing LDAP configuration database...done.
Setting defaults...No results returned for A lookup of centos7.ehowstuff.local
Checked nameservers:
192.168.0.70
No results returned for AAAA lookup of centos7.ehowstuff.local
Checked nameservers:
192.168.0.70
DNS ERROR resolving centos7.ehowstuff.local
It is suggested that the hostname be resolvable via DNS
Change hostname [Yes]
Please enter the logical hostname for this host [centos7.ehowstuff.local] mail.example.com
No results returned for A lookup of mail.example.com
Checked nameservers:
192.168.0.70
DNS ERROR resolving mail.example.com
It is suggested that the hostname be resolvable via DNS
Re-Enter hostname [Yes]
Please enter the logical hostname for this host [centos7.ehowstuff.local] mail.example.local
DNS ERROR resolving MX for mail.example.local
It is suggested that the domain name have an MX record configured in DNS
Change domain name? [Yes]
Create domain: [mail.example.local] example.local
MX: mail.example.local (192.168.0.70)
Interface: 127.0.0.1
Interface: ::1
Interface: 192.168.0.70
done.
Checking for port conflicts
Main menu
1) Common Configuration:
2) zimbra-ldap: Enabled
3) zimbra-logger: Enabled
4) zimbra-mta: Enabled
5) zimbra-snmp: Enabled
6) zimbra-store: Enabled
+Create Admin User: yes
+Admin user to create: admin@example.local
******* +Admin Password UNSET
+Anti-virus quarantine user: virus-quarantine.fsbv7fj6r0@example.local
+Enable automated spam training: yes
+Spam training user: spam.7xlmrmrh3@example.local
+Non-spam(Ham) training user: ham.rt_1on1o@example.local
+SMTP host: mail.example.local
+Web server HTTP port: 8080
+Web server HTTPS port: 8443
+Web server mode: https
+IMAP server port: 7143
+IMAP server SSL port: 7993
+POP server port: 7110
+POP server SSL port: 7995
+Use spell check server: yes
+Spell server URL: http://mail.example.local:7780/aspell.php
+Enable version update checks: TRUE
+Enable version update notifications: TRUE
+Version update notification email: admin@centos7.ehowstuff.local
+Version update source email: admin@centos7.ehowstuff.local
+Install mailstore (service webapp): yes
+Install UI (zimbra,zimbraAdmin webapps): yes
7) zimbra-spell: Enabled
8) zimbra-proxy: Enabled
9) Enable VMware HA: no
10) Default Class of Service Configuration:
s) Save config to file
x) Expand menu
q) Quit
Address unconfigured (**) items (? - help) 6
Store configuration
1) Status: Enabled
2) Create Admin User: yes
3) Admin user to create: admin@example.local
** 4) Admin Password UNSET
5) Anti-virus quarantine user: virus-quarantine.fsbv7fj6r0@example.local
6) Enable automated spam training: yes
7) Spam training user: spam.7xlmrmrh3@example.local
8) Non-spam(Ham) training user: ham.rt_1on1o@example.local
9) SMTP host: mail.example.local
10) Web server HTTP port: 8080
11) Web server HTTPS port: 8443
12) Web server mode: https
13) IMAP server port: 7143
14) IMAP server SSL port: 7993
15) POP server port: 7110
16) POP server SSL port: 7995
17) Use spell check server: yes
18) Spell server URL: http://mail.example.local:7780/aspell.php
19) Enable version update checks: TRUE
20) Enable version update notifications: TRUE
21) Version update notification email: admin@centos7.ehowstuff.local
22) Version update source email: admin@centos7.ehowstuff.local
23) Install mailstore (service webapp): yes
24) Install UI (zimbra,zimbraAdmin webapps): yes
Select, or 'r' for previous menu [r] 4
Password for admin@example.local (min 6 characters): [SBmeBXtA] password
Store configuration
1) Status: Enabled
2) Create Admin User: yes
3) Admin user to create: admin@example.local
4) Admin Password set
5) Anti-virus quarantine user: virus-quarantine.fsbv7fj6r0@example.local
6) Enable automated spam training: yes
7) Spam training user: spam.7xlmrmrh3@example.local
8) Non-spam(Ham) training user: ham.rt_1on1o@example.local
9) SMTP host: mail.example.local
10) Web server HTTP port: 8080
11) Web server HTTPS port: 8443
12) Web server mode: https
13) IMAP server port: 7143
14) IMAP server SSL port: 7993
15) POP server port: 7110
16) POP server SSL port: 7995
17) Use spell check server: yes
18) Spell server URL: http://mail.example.local:7780/aspell.php
19) Enable version update checks: TRUE
20) Enable version update notifications: TRUE
21) Version update notification email: admin@centos7.ehowstuff.local
22) Version update source email: admin@centos7.ehowstuff.local
23) Install mailstore (service webapp): yes
24) Install UI (zimbra,zimbraAdmin webapps): yes
Select, or 'r' for previous menu [r] 21
Version update destination address: [admin@centos7.ehowstuff.local] admin@example.local
Store configuration
1) Status: Enabled
2) Create Admin User: yes
3) Admin user to create: admin@example.local
4) Admin Password set
5) Anti-virus quarantine user: virus-quarantine.fsbv7fj6r0@example.local
6) Enable automated spam training: yes
7) Spam training user: spam.7xlmrmrh3@example.local
8) Non-spam(Ham) training user: ham.rt_1on1o@example.local
9) SMTP host: mail.example.local
10) Web server HTTP port: 8080
11) Web server HTTPS port: 8443
12) Web server mode: https
13) IMAP server port: 7143
14) IMAP server SSL port: 7993
15) POP server port: 7110
16) POP server SSL port: 7995
17) Use spell check server: yes
18) Spell server URL: http://mail.example.local:7780/aspell.php
19) Enable version update checks: TRUE
20) Enable version update notifications: TRUE
21) Version update notification email: admin@example.local
22) Version update source email: admin@centos7.ehowstuff.local
23) Install mailstore (service webapp): yes
24) Install UI (zimbra,zimbraAdmin webapps): yes
Select, or 'r' for previous menu [r] 22
Version update source address: [admin@centos7.ehowstuff.local] admin@example.local
Store configuration
1) Status: Enabled
2) Create Admin User: yes
3) Admin user to create: admin@example.local
4) Admin Password set
5) Anti-virus quarantine user: virus-quarantine.fsbv7fj6r0@example.local
6) Enable automated spam training: yes
7) Spam training user: spam.7xlmrmrh3@example.local
8) Non-spam(Ham) training user: ham.rt_1on1o@example.local
9) SMTP host: mail.example.local
10) Web server HTTP port: 8080
11) Web server HTTPS port: 8443
12) Web server mode: https
13) IMAP server port: 7143
14) IMAP server SSL port: 7993
15) POP server port: 7110
16) POP server SSL port: 7995
17) Use spell check server: yes
18) Spell server URL: http://mail.example.local:7780/aspell.php
19) Enable version update checks: TRUE
20) Enable version update notifications: TRUE
21) Version update notification email: admin@example.local
22) Version update source email: admin@example.local
23) Install mailstore (service webapp): yes
24) Install UI (zimbra,zimbraAdmin webapps): yes
Select, or 'r' for previous menu [r] r
Main menu
1) Common Configuration:
2) zimbra-ldap: Enabled
3) zimbra-logger: Enabled
4) zimbra-mta: Enabled
5) zimbra-snmp: Enabled
6) zimbra-store: Enabled
7) zimbra-spell: Enabled
8) zimbra-proxy: Enabled
9) Enable VMware HA: no
10) Default Class of Service Configuration:
s) Save config to file
x) Expand menu
q) Quit
*** CONFIGURATION COMPLETE - press 'a' to apply
Select from menu, or press 'a' to apply config (? - help) a
Save configuration data to a file? [Yes]
Save config in file: [/opt/zimbra/config.23920]
Saving config in /opt/zimbra/config.23920...done.
The system will be modified - continue? [No] yes
Operations logged to /tmp/zmsetup01032015-084819.log
Setting local config values...done.
Initializing core config...Setting up CA...done.
Deploying CA to /opt/zimbra/conf/ca ...done.
Creating SSL zimbra-store certificate...done.
Creating new zimbra-ldap SSL certificate...done.
Creating new zimbra-mta SSL certificate...done.
Creating new zimbra-proxy SSL certificate...done.
Installing mailboxd SSL certificates...done.
Installing MTA SSL certificates...done.
Installing LDAP SSL certificate...done.
Installing Proxy SSL certificate...done.
Initializing ldap...done.
Setting replication password...done.
Setting Postfix password...done.
Setting amavis password...done.
Setting nginx password...done.
Setting BES searcher password...done.
Creating server entry for mail.example.local...done.
Setting Zimbra IP Mode...done.
Saving CA in ldap ...done.
Saving SSL Certificate in ldap ...done.
Setting spell check URL...done.
Setting service ports on mail.example.local...done.
Setting zimbraFeatureTasksEnabled=TRUE...done.
Setting zimbraFeatureBriefcasesEnabled=TRUE...done.
Setting TimeZone Preference...done.
Initializing mta config...done.
Setting services on mail.example.local...done.
Adding mail.example.local to zimbraMailHostPool in default COS...done.
Creating domain example.local...done.
Setting default domain name...done.
Creating domain example.local...already exists.
Creating admin account admin@example.local...done.
Creating root alias...done.
Creating postmaster alias...done.
Creating user spam.7xlmrmrh3@example.local...done.
Creating user ham.rt_1on1o@example.local...done.
Creating user virus-quarantine.fsbv7fj6r0@example.local...done.
Setting spam training and Anti-virus quarantine accounts...done.
Initializing store sql database...done.
Setting zimbraSmtpHostname for mail.example.local...done.
Configuring SNMP...done.
Setting up syslog.conf...done.
Starting servers...done.
Installing common zimlets...
com_zimbra_proxy_config...done.
com_zimbra_mailarchive...done.
com_zimbra_attachmail...done.
com_zimbra_url...done.
com_zimbra_phone...done.
com_zimbra_date...done.
com_zimbra_ymemoticons...done.
com_zimbra_clientuploader...done.
com_zimbra_srchhighlighter...done.
com_zimbra_tooltip...done.
com_zimbra_webex...done.
com_zimbra_bulkprovision...done.
com_zimbra_email...done.
com_zimbra_adminversioncheck...done.
com_zimbra_cert_manager...done.
com_zimbra_viewmail...done.
com_zimbra_attachcontacts...done.
Finished installing common zimlets.
Restarting mailboxd...done.
Creating galsync account for default domain...done.
You have the option of notifying Zimbra of your installation.
This helps us to track the uptake of the Zimbra Collaboration Server.
The only information that will be transmitted is:
The VERSION of zcs installed (8.6.0_GA_1153_RHEL7_64)
The ADMIN EMAIL ADDRESS created (admin@example.local)
Notify Zimbra of your installation? [Yes] no
Notification skipped
Setting up zimbra crontab...done.
Moving /tmp/zmsetup01032015-084819.log to /opt/zimbra/log
Configuration complete - press return to exit
5. Start zimbra services :
su - zimbra zmcontrol start