Showing posts with label RHEL 7. Show all posts

GNOME : How to add Custom Folder links to left panel

Are you looking the way to Add Folder Shortcut To Left Panel File Browser ( Places ).

Toggle into the directory you want to make a shortcut and hit Ctrl+D from your keyboard

Lets take an example

I want a folder named as NIB to be appear into the left panel of file browser.

Toggle into NIB and simply hit Ctrl+D

I hope this help you..

FIX : PHPMyAdmin Error - Table 'phpmyadmin.pma_table_uiprefs' doesn't exist

Locate config.inc.php within phpMyAdmin folder.

Find and edit the below mentioned line .

       

$ Cfg ['Servers'] [$ i] ['table_uiprefs'] = ‘pma_table_uiprefs’;

Into

       

$ cfg ['Servers'] [$ i] ['pma__table_uiprefs'] = ‘pma__table_uiprefs’;

       

Finally to apply the changes Restart Apache

MariaDB Startup error Fix : mysqld: Can't create/write to file '/var/run/mariadb/mariadb.pid' (Errcode: 2)

170529 15:34:47 [ERROR] mysqld: Can't create/write to file '/var/run/mariadb/mariadb.pid' (Errcode: 2)
170529 15:34:47 [ERROR] Can't start server: can't create PID file: No such file or directory
170529 15:34:47 mysqld_safe mysqld from pid file /var/run/mariadb/mariadb.pid ended

Description of problem:
When I restart my RHEL 7 box, the mariadb service will not start, due to /var/run/mariadb not existing.

Version : mariadb-server-5.5.52-1.el7.x86_64

MariaDB isn't running, and you can't start it manually:

$ systemctl start mariadb

Error Lines.

170529 15:34:47 [Note] Server socket created on IP: '0.0.0.0'.
170529 15:34:47 [ERROR] mysqld: Can't create/write to file '/var/run/mariadb/mariadb.pid' (Errcode: 2)
170529 15:34:47 [ERROR] Can't start server: can't create PID file: No such file or directory
170529 15:34:47 mysqld_safe mysqld from pid file /var/run/mariadb/mariadb.pid ended






Additional info:
Fix this by creating the missing folder in the tmpfs and setting permission to mariadb:

# install -dpm770 -o mysql -g mysql /var/run/mariadb
# systemctl start mariadb

Linux Command to find Hard disk serial number and details.

Most of the times, when a linux system contains more then 1 hard drives and during the process of re installation to keep the user data safe and simply format the system without effecting the user data placed in another physical drive, we face challenges while discriminating hardisks by sda, sdb, sdc

The best approach is to identify the hard disk serial number and the apply actions accordingly.

So in my case i have two hard disks as sda and sdb one hard disk has system files and configurations and one has user data

I have identified this using pvs command

[root@cyberkeeda ~]# pvs

PV VG Fmt Attr PSize PFree
/dev/sda2 rootvg lvm2 a--u 465.25g 0

/dev/sdb1 homevg lvm2 a--u 465.75g 0

I can easily identify from here, which hdd has root file, system files installed within it.

here sda -- system files

sdb -- user data

Find the hard disk details from the below mentioned commands.

hdparm

[root@cyberkeeda ~]# hdparm -I /dev/sd? | grep 'Serial\ Number'

Output will look like

Serial Number: WD-WCC2SFS30435

Serial Number: WD-WCC2HEFS25680

One can also use lshw or smartctl to fetch more details of hard drives

lshw

[root@cyberkeeda ~]# lshw -class disk

smartctl

[root@cyberkeeda ~]# smartctl -i /dev/sda

If you are missing those tools, just install following packages

# apt-get install smartmontools

# yum install smartmontools

# apt-get install lshw

# yum install lshw

The 'oslo_middleware.ssl' module usage is deprecated, please use oslo_middleware.http_proxy_to_wsgi instead

The problem was as simple as nothing but it really troubled me a lot, i have googled a lot so you don't have to.

I was trying to upload a centos image which was in qcow format, i processed everything but i don't know it gives a lot of errors while doing it.

Some of that I can see within my Horizon was

Horizon image upload failed - Danger error submitting form

Failed to list images

I'm new to Openstack but still got to know that GLANCE is responsible for the imaging part in Horizon.

Went through the log file of glance at tail -100f /var/log/glance/api.log

And found some lines error to connect at my ip with 9292 port, i somehow figured out it is relevant with the glance-api , tried to netstat the port but could not find anything.

Found solution from some website as start the glance services

glance-control all status
glance-control all start

it might can help, but I was not that much lucky at all, some blog suggested me to run command as

# glance-api

The moment i run that command well some python error was there and it was

The 'oslo_middleware.ssl' module usage is deprecated, please use oslo_middleware.http_proxy_to_wsgi instead

I searched more and more then accidentally found one of my installed oslo package contains bug that leads to the eroor

python2-oslo-middleware-3.19.0-1.el7.noarch

This specific version has this bug associated with it, you can overcome this by installing

oslo.middleware-3.20 or more

I have downloaded this from internet and installed the python package using pip

# pip install oslo.middleware-3.23.1.tar.gz

Offcourse it has some dependency , but you can sort it out at your own iknow