Skip to main content

List and explain all the status files in NFS.

By
64.List and explain all the status files in NFS.
Ans.
1. /var/lib/nfs.rmtab – It list each NFS export that is mounted by an NFS client. It uses the Daemon rpc.mountd since it is responsible for servicing the request to mount NFS exports.
Whenever , rpc.mounted daemon receives request, it adds an entry into /var/lib/nfs/rmtab. The same goes for unmounts request but in that case entry is removed from status file.

 2. /var/lib/nfs/etab – It contains list of currently exported filesystem, the exportfs command maintains the entries in this file.

 3. These three scripts which are initialized and controls the required NFS server daemons /etc/rc.d/init.d/portmap
/etc/rc.d/init.d/nfs
/etc/rc.d/init.d/nfslock

 4. The portmap scripts starts the portmap daemon also called as portmapper. All programs that uses RPC, such as NIS and NFS, depends on the information the portmapper provides.

 5. The primary NFS startup script is /etc/rc.d/init.d/nfs, It requires single argument. E.g. start, stop, restart or reloaded. These commands are executed as follows:
#service nfs status
#service nfs stop
#service nfs start
#service nfs restart
#service nfs reload

 6. NFS service also requires the file locking daemons lockd and statd. Lockd is started automatically but statd is started separately. To carry out this process initialization script can also be useful i.e. /etc/rc.d/init.d/nfslock

Labels:

Comments

Post a Comment

Popular posts from this blog

Explain the tools used to monitor system security.

By
12.Explain the tools used to monitor system security. Ans. 1. People who, for purpose of larceny or to amuse themselves, like to break into computers, they are called ‘crackers’. 2. If there is a vulnerability in a system they will find it and use it against you. 3. Preventing use of your machine for nefarious purpose and guarding against intrusion are, in the end, your responsibility alone. 4. Red hat equips you with tools to detect and deal with unauthorised access of many kinds. 5. You need to configure those tools and understand how to sense the warning they provide. 6. Fortunately Linux is development community is quick to find potential exploits and to create ways of slamming the doors before crackers can enter in your system. 7. Red hat is careful enough to making available new, patched version in which potential exploits have been found. 8. You should make sure to download and install the repaired package. 9. This line of defence...
Post a Comment
Read more

Explain the file systems supported by Linux.

By
21.Explain the file systems supported by Linux. Ans. 1. Linux can read/write to several file system that originated with other operating system much different from Linux. 2. One reason that Linux supports so many file systems is the design of its virtual file system (VFS) layer, its provides a fairly universal forms of file support, file systems supported by Linux are as follows: 3. ext3: • Ext3 stands for third extended file system. • Starting from Linux Kernel 2.4.15 ext3 was available. • The main benefit of ext3 is that it allows journaling. • Journaling has a dedicated area in the file system, where all the changes are tracked. • When the system crashes, the possibility of file system corruption is less because of journaling. (If no journaling, then fsck command (file system consistency check) is used to check for the corrupted file and to repair that file). • ext3 keeps a record of uncommitted file transactions and applies only those transactions when the sy...
Post a Comment
Read more

Explain the boot process in Linux.

By
13.Explain the boot process in Linux. Ans. 1. When we turn on our PC, it runs a program called “Basic input/output System” (BIOS). 2. BIOS is the only way to communicate with the system components until the operating system is up and running and able to take over the system management functions. 3. BIOS is installed on Read only memory (ROM) chip physically attached to system board. 4. The ROM type of chip is usually referred as to as an EEPROM chip, meaning it’s not writeable by user. 5. After the BIOS loads, it performs some diagnostics on the hardware, checks the installed components to be sure they are functioning and checks the system RAM (Random access memory). 6. Next the BIOS tries to find system drives from which it can load the boot program to begin the process of starting the operating system/kernel. 7. We can specify the search order for drives by changing the setting in the system BIOS configuration. 8. Usually the first hard drive...
Post a Comment
Read more