Posts from the ‘Linux’ Category

Oracle Linux 7.4 harddisk partition

You have two HDD and need to make two partition with separate during installation

yum install package compilation issue

I created a local repository in redhat 7.6 and then i am trying to install the package but i am getting the dependency issue.

Error :

[root@ebs-117-41 Packages]# yum install glibc-2.17-222.el7.i686
Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager
This system is not registered with an entitlement server. You can use subscription-manager to register.
Resolving Dependencies
–> Running transaction check
—> Package glibc.i686 0:2.17-222.el7 will be installed
–> Processing Dependency: glibc-common = 2.17-222.el7 for package: glibc-2.17-222.el7.i686
–> Processing Dependency: libfreebl3.so(NSSRAWHASH_3.12.3) for package: glibc-2.17-222.el7.i686
–> Processing Dependency: libfreebl3.so for package: glibc-2.17-222.el7.i686
–> Running transaction check
—> Package glibc.i686 0:2.17-222.el7 will be installed
–> Processing Dependency: glibc-common = 2.17-222.el7 for package: glibc-2.17-222.el7.i686
—> Package nss-softokn-freebl.i686 0:3.34.0-2.el7 will be installed
–> Finished Dependency Resolution
Error: Package: glibc-2.17-222.el7.i686 (customrepo)
Requires: glibc-common = 2.17-222.el7
Installed: glibc-common-2.17-260.el7.x86_64 (@anaconda/7.6)
glibc-common = 2.17-260.el7
Available: glibc-common-2.17-222.el7.x86_64 (customrepo)
glibc-common = 2.17-222.el7
You could try using –skip-broken to work around the problem
You could try running: rpm -Va –nofiles –nodigest

Solution :

By mistake I created a local repository with lower version of redhat. so that it’s not compatible when i try to install rpm packages. After i corrected the repository version, it’s okay to install.

In case, If you still continue to see the error after you created the repository with correct version, you need to clean.

yum clean all

then execute

yum repolist

Now We can able to install rpm packages on the server using local repository.

reclaim reserved available free space on linux

reclaim reserved available free space

[root@dbs-xxx-4-131 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol01
65G 2.7G 59G 5% /
/dev/mapper/VolGroup01-LogVol00
679G 35G 609G 6% /u01
/dev/sda1 996M 46M 899M 5% /boot
tmpfs 7.8G 0 7.8G 0% /dev/shm
/dev/sdc1 886G 200M 841G 1% /Backup

[root@dbs-ruh-4-131 ~]# tune2fs -m 0 /dev/sdc1
tune2fs 1.39 (29-May-2006)
Setting reserved blocks percentage to 0% (0 blocks)

[root@dbs-xxx-4-131 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol01
65G 2.7G 59G 5% /
/dev/mapper/VolGroup01-LogVol00
679G 35G 609G 6% /u01
/dev/sda1 996M 46M 899M 5% /boot
tmpfs 7.8G 0 7.8G 0% /dev/shm
/dev/sdc1 886G 200M 886G 1% /Backup

Oracle Linux 7.6 black screen while boot from virtualbox

I am trying to boot my oracle linux 7.6 which is running under virtual box but black screen appear long time

Causes :

Network manager & network manager wait online service have a problem

Solution :

Boot as rescue mode like below

Edit mode (e)

end of line linux16, add below command

systemd.unit=target.rescue

control + x  –> enter

Maintenance mode will appear

Enter root password maintenance

Execute below command

systemctl mask systemd-NetworkManager-wait-online.service

reboot the machine

The network manager may have a problem after restarted the machine, so start the network manager like below

systemctl enable NetworkManager

systemctl unmask NetworkManager.service

systemctl start NetworkManager.service

In case selinux may also making issue for black screen appeared while booting. Please disable and reboot the machine.

Logical volume group partition inactive

We rebooted a one of our linux machine which is running a database, After rebooted We can’t able to start the database due to the one of partition of the logical volume group has missing.

[root@ezylebuat ~]# pvs
WARNING: Device for PV EiG4AR-8JDt-bzEj-5si7-Wf4z-xrYC-a8zXgu not found or rejected by a filter.
WARNING: Device for PV HfPGnn-1bgb-j1HH-7Xvd-6hvq-yk14-jMCrkM not found or rejected by a filter.
PV VG Fmt Attr PSize PFree
/dev/sda2 ol lvm2 a– <199.00g 0
[unknown] ol lvm2 a-m <50.00g 0
[unknown] ol lvm2 a-m <50.00g <50.00g

[root@ezylebuat ~]# lvscan
WARNING: Device for PV EiG4AR-8JDt-bzEj-5si7-Wf4z-xrYC-a8zXgu not found or rejected by a filter.
WARNING: Device for PV HfPGnn-1bgb-j1HH-7Xvd-6hvq-yk14-jMCrkM not found or rejected by a filter.
inactive ‘/dev/ol/u01’ [<167.00 GiB] inherit
ACTIVE ‘/dev/ol/swap’ [<32.00 GiB] inherit
ACTIVE ‘/dev/ol/home’ [25.00 GiB] inherit
ACTIVE ‘/dev/ol/root’ [25.00 GiB] inherit

Solution :

activate the volume group

[root@ezylebuat ~]# vgchange -a y –partial ol
PARTIAL MODE. Incomplete logical volumes will be processed.
WARNING: Device for PV EiG4AR-8JDt-bzEj-5si7-Wf4z-xrYC-a8zXgu not found or rejected by a filter.
WARNING: Device for PV HfPGnn-1bgb-j1HH-7Xvd-6hvq-yk14-jMCrkM not found or rejected by a filter.
4 logical volume(s) in volume group “ol” now active

[root@ezylebuat ~]# df -h
Filesystem Size Used Avail Use% Mounted on
devtmpfs 7.7G 0 7.7G 0% /dev
tmpfs 7.8G 0 7.8G 0% /dev/shm
tmpfs 7.8G 8.9M 7.8G 1% /run
tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup
/dev/mapper/ol-root 25G 16G 9.5G 63% /
/dev/mapper/ol-home 25G 39M 25G 1% /home
tmpfs 1.6G 40K 1.6G 1% /run/user/0
/dev/sda1 1014M 266M 749M 27% /boot
/dev/sdb1 99G 31G 63G 34% /backup
/dev/mapper/ol-u01 117G 101G 17G 86% /u01

[root@ezylebuat ~]# lvdisplay
WARNING: Device for PV EiG4AR-8JDt-bzEj-5si7-Wf4z-xrYC-a8zXgu not found or rejected by a filter.
WARNING: Device for PV HfPGnn-1bgb-j1HH-7Xvd-6hvq-yk14-jMCrkM not found or rejected by a filter.
— Logical volume —
LV Path /dev/ol/u01
LV Name u01
VG Name ol
LV UUID OoQvh4-9PRs-zVY3-ZFbO-SGn9-qUng-iJR2wL
LV Write Access read/write
LV Creation host, time localhost.localdomain, 2018-01-17 11:43:54 +0300
LV Status available
# open 1
LV Size <167.00 GiB
Current LE 42751
Segments 2
Allocation inherit
Read ahead sectors auto
– currently set to 8192
Block device 249:4

After volume group activated , I can able to start the database . Even though  I can see the some of the HDD server failure, So  I plan to migrate the database to other machine.

mailx sender address picks the OS user account instead of sender address

We’re trying to send email from redhat 7 terminal using with below command,

mailx -s “Test mail” mazar@xxxx.com -r ezylebdb@alerts.xxxx.net

But its sender by OS hostname

Solution :

Send by like below

mailx -r ezylebdb@alerts.xxxx.net -s “Test mail” mazar@xxxx.com

creating local repository yum install linux

Follow the below procedure

[root@ebs-app-xx-xx u01]# yum repolist

[root@ebs-app-xx-xx u01]# yum list installed | grep createrepo

createrepo.noarch                         0.9.9-28.el7             @anaconda/7.5

[root@ebs-app-xx-xx u01]# createrepo /u01/Packages/

[root@ebs-app-xx-xx u01]# cd /etc/yum.repos.d

[root@ebs-app-xx-xx yum.repos.d]# ls -tlr

total 4

-rw-r–r–. 1 root root 358 Nov  4 22:55 redhat.repo

Now, create custom repository

[root@ebs-app-xx-xx yum.repos.d]# cat custom.repo

[customrepo]

name=Custom Repository

baseurl=file:///u01/Packages/

enabled=1

gpgcheck=0

you can check how much packages in the repository

[root@ebs-app-xx-xx yum.repos.d]# yum repolist

Now, we can install the rpm packages from the repository

[root@ebs-app-xx-xx Packages]# yum install tigervnc-1.8.0-5.el7.x86_64.rpm

Redhat 7 :

cat custom.repo
[customrepo]
name=Custom Repository
baseurl=file:///u01/install/Packages/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

[root@ebs-117-41 yum.repos.d]# yum clean all
Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager
This system is not registered with an entitlement server. You can use subscription-manager to register.
Cleaning repos: customrepo
[root@ebs-117-41 yum.repos.d]# yum repolist enabled

Issue faced :

if  repository giving below error message,then your repository is corrupted.

Error Downloading Packages:

InstallMedia: [Errno 256] No more mirrors to try.

Solution:

Refer

https://access.redhat.com/solutions/203603

Remove this file if there is no X server

Try to start VNC, you may get the below error

[root@fusiondev ~]# vncserver

Warning: fusiondev.xxxxx.com:1 is taken because of /tmp/.X1-lock
Remove this file if there is no X server fusiondev.xxxx.com:1

New ‘fusiondev.xxxxx.com:2 (root)’ desktop is fusiondev.xxxxx.com:2

Starting applications specified in /root/.vnc/xstartup
Log file is /root/.vnc/fusiondev.xxxxx.com:2.log

Solution :

[root@fusiondev tmp]# rm -rf /tmp/.X1-lock

[root@fusiondev tmp]# rm -rf /tmp/.X11-unix/X1

[root@fusiondev tmp]# vncserver

New ‘fusiondev.xxxxxx.com:1 (root)’ desktop is fusiondev.xxxxxx.com:1

Starting applications specified in /root/.vnc/xstartup
Log file is /root/.vnc/fusiondev.xxxxxx:1.log

Start and stop firewall OEL 7

Check the status

[root@ezylebuat ~]# systemctl status firewalld
● firewalld.service – firewalld – dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: enabled)
Active: active (running) since Wed 2018-01-17 06:37:59 EST; 24min ago

Stop the firewall

[root@ezylebuat ~]# systemctl  stop firewalld 

[root@ezylebuat ~]# systemctl status firewalld
● firewalld.service – firewalld – dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: enabled)
Active: inactive (dead) since Wed 2018-01-17 07:04:09 EST; 3s ago
Docs: man:firewalld(1)

Disable the firewall( After reboot,It will not enable automatically)

[root@ezylebuat ~]# systemctl disable firewalld

Enable the firewall

[root@ezylebuat ~]# systemctl enable firewalld

Start the firewall

[root@ezylebuat ~]# systemctl  firewalld start

find the files older than 30 days in linux

cd /u01/app/12c/oracle/trace

find *.trc -maxdepth 1 -mtime +30 -type f -exec ls -l {} \;