Server Administration & Management

Difference between NAS & SAN

S.No. NAS – Network Attached Storage SAN – Storage Area Network
1 It can be mapped as network drives to share on that server. It can be used as a ‘disk in disk’ and volume management utilities.
2 It provides storage and a file system. It provide Block based storage.
3 Protocols –> NFS, CIFS & SMB Protocols –> SCSI, Fibre Channel, iSCSI, ATA over Ethernet & HyperSCSI
4 For small & medium business For large organizations
5 Storage Capacity –> up to few TB Storage Capacity –> Many TB
6 Multiple NAS Devices Single SAN & Multiple high performance disk arrays
7 Specialized knowledge and training is not required to configure and maintain NAS. Specialized knowledge and training is required to configure and maintain SANs.
8 NAS & SAN are not mutually exclusive. A hybrid of SAN and NAS can offer file and block level protocols from the same system to support NAS and SAN.

June 30, 2014 Posted by | SAN, Tips & Tricks, Unix/Linux | , , , | Leave a comment

How to find UUID of devices in Linux

This trick is for those who deal with many removable devices, with every device changing its name after you restart your systm. The solution is to mount devices by using their UUIDs (Universally Unique Identifier)

# blkid

/dev/sda1: UUID=”0bd49e6e-6692-410e-8408-5353905f5c42″ TYPE=”ext4″
/dev/sda2: UUID=”cea4d6d2-d624-4193-9576-67ec27b15796″ TYPE=”ext4″
/dev/sda3: UUID=”3b00985c-cf8d-4b87-be92-74186d0a2dcb” TYPE=”ext4″
/dev/sda5: UUID=”79b4e73d-d40d-428b-86a8-930506d86d8d” TYPE=”swap”

Which will show the UUIDs of devices, Now you can make an entry in the “/etc/fstab” file to avoid any problems.
This tip can also be applied in case of SAN storage, where every Logical Unit Number (LUN) needs to be mounted.

June 20, 2014 Posted by | Tips & Tricks, Unix/Linux | , , | Leave a comment

How to find Hardware information on Live (running) Servers & Systems

dmidecode is a tool for dumping a computer DMI (some say SMBIOS) table contents in a human-readable format. This table contains a description of the system hardware components, as well as other useful pieces of information such as serial numbers  and  BIOS  revision.  You can retrieve this information without having to probe for the actual hardware.  While this is a good point in terms of report speed and safeness, this also makes the presented information possibly unreliable.

The  DMI  table  does not  only describe what the system is currently made of, it also can report the possible evolutions (such as the fastest supported CPU or the maximal amount of memory supported).

SMBIOS stands for System Management BIOS, while DMI stands for Desktop Management Interface. Both standards are  tightly related and developed by the DMTF (Desktop Management Task Force).

# yum install dmidecode

# dmidecode –type bios [About BIOS Details]

# dmidecode –type system [About System Information]

# dmidecode –type baseboard [About NIC & Storage Card Information]

# dmidecode –type chassis [About Chassis Information]

# dmidecode –type processor [About Processor Information]

# dmidecode –type memory [About Memory Information]

# dmidecode –type cache [About Cache Information]

# dmidecode –type connector [About USB Information]

# dmidecode –type slot [About Slot Information]

June 10, 2014 Posted by | Tips & Tricks, Unix/Linux | , , | Leave a comment