Sys Admin

Just to test the ceph bluestore i have created 2 virtual machine in virtualbox with hostname: admin & osd1. Attached the 2 10G hdd for the OSD's in both the nodes. Below are the commands that i used to deploy it using the ceph-ansible: git clone https://github.com/ceph/ceph-ansible cd ceph-ansible cp group_vars/osds.yml.sample group_vars/osds.yml cp group_vars/all.yml.sample group_vars/all.yml cp group_vars/mons.yml.sample group_vars/mons.yml cp site.yml.sample site.yml vi group_vars/osds.yml     devices:    - /dev/sdb     - /dev/sdc bluestore : true vi group_vars/all.yml ceph_stable: true ceph_mirror: http://download.ceph.com/ ceph_stable_key: https://download.ceph.com/keys/release.asc ceph_stable_release: kraken ceph_stable_repo: "{{ ceph_mirror }}/rpm-{{ ceph_stable_release }}" monitor_interface: enp0s3 monitor_address: 192.xx.xx.xx osd_objectstore: bluestore ceph_conf_overrides:  ...

Using in-built command : root@abcd~# ethtool <ethX> for eg: root@abcd~# ethtool eth0 Settings for eth0: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Supports auto-negotiation: Yes Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Advertised pause frame use: No Advertised auto-negotiation: Yes Speed: 1000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 1 Transceiver: internal Auto-negotiation: on MDI-X: on Supports Wake-on: pumbg Wake-on: g Current message level: 0x00000001 (1) Link detected: yes check the last line if it shows yes then that ethernet port is up. OR root@abcd~# dmesg | grep eth ...

Here we will see a technique  how to spoof MAC address in Linux . MAC address spoofing is changing the Media Access Control (MAC) address of the network interface card (NIC). First of all let me tell you that the MAC address or the Hardware address is inbuilt and is actually burnt into your NIC interface card at the time of manufacturing. It is unique worldwide and cannot be changed permanently by the use of any kind of software. That being said, however we can change it temporarily to suit our needs. The method described here can be used in RHEL, CentOS and Ubuntu as well. MAC address is 48 bits hexadecimal address. Before directly changing the address you need to find out the current MAC address of your network card by using the command # ifconfig | grep HWADDR It will give you output as eth0 Link encap:Ethernet HWaddr 00:21:5A:9B:00:F0 The MAC address in this case is 00:21:5A:9B:00:F0 How to spoof / change MAC address in Linux To change it use the ifconfig...

To verify if a system is 32 bit versus 64 bit you can use the uname command. Below are examples of using the uname command from the CLI on a 32 bit system followed by using the uname command on a 64 bit system. 32 Bit CentOS Linux Server 1 [root@server ~] # uname -a 2 Linux server1.example.com 2.6.18-92.1.13.el5 #1 SMP Wed Sep 24 19:33:52 EDT 2008 i686 i686 i386 GNU/Linux 64 Bit CentOS Linux Server 1 [root@server ~] # uname -a 2 Linux server.example.com 2.6.18-53.1.21.el5 #1 SMP Tue May 20 09:35:07 EDT 2008 x86_64 x86_64 x86_64 GNU/Linux As you can see above the 64 bit server will show x86_64 numerous times after the install date and time. The 32 bit system will show i686 and i386 after the install date and time. So it is very easy to verify if a system is 32 bit versus 64 bit using the “uname -a” command from a shell.