Linux Interview Questions and Answers
Question - 61 : - How to set the mask permanently for a user?
Answer - 61 : -
If the unmask command invoked without any arguments, it means it will display the current mask.
To set the unmask permanently, we have two types.
They are:
- Ocotal representation.
- Symbolic representation.
Question - 62 : - What is network bonding in Linux?
Answer - 62 : -
Network Bonding is a process of combining more than two network interfaces to form a single network interface. It offers performance improvement and redundancy by increasing network throughput and bandwidth.
No need to worry if one interface is down or unplugged because the other will work. The behaviour of the bonded interface depends on the bonding method.
Question - 63 : - What are the different modes of Network bonding in Linux?
Answer - 63 : -
Different modes of Linux network bonding
- Mode-0(balance-rr): It is a default mode and based on Round-Robin policy. It offers fault tolerance and load balancing features. It used round-robin fashion to transmit the packets.
- Mode-1(active-backup): It is based on Active Backup policy and only one slave will act in the band and another one will act when the others fail in the band. It also provides fault tolerance.
- Mode-2(balance-xor): It sets a xor mode between the source Mac address and destination Mac address to provide fault tolerance.
- Mode-3(broadcast): It is based on broadcast policy and transmitted everything in the slave interface. It also provides fault tolerance and can be used only for a particular purpose.
- Mode-4(802.3ad): It is a dynamic aggregation mode, it created aggregation groups which is having the same speed. It uses the transmit hashing method to select the slaves for outgoing traffic.
- Mode-5(balance-tlb): The outgoing traffic is according to the current load on the slave, and the incoming traffic is received by the slave. It is called an adaptive transmit load balancing mode.
- Mode-6(balance-alb): It is an adaptive load balancing mode. It does not require any switch support.
Question - 64 : - How to check the default route and routing table?
Answer - 64 : -
To display the default route and routing table, we use the following commands.
$ route-n
$ nestat-rn
$ ip
Question - 65 : - What is lsof command in Linux?
Answer - 65 : -
lsof means List of files, we can know which file is opened by which process.
#lsof
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Question - 66 : - What is netstat command in Linux?
Answer - 66 : -
netstat command gives various information about the network and routing tables, interface statics and more about the system.
Question - 67 : - What is the top Command in Linux?
Answer - 67 : -
The top command is used to show the system process and it displays and updates the sorted process information.
Question - 68 : - What is ps command in Linux?
Answer - 68 : -
The ps command displays the current process status of the system. And it displays the processes id’s with some other related data also.
Syntax:
Ps [options]
Question - 69 : - What is grep command in Linux?
Answer - 69 : -
grep command is a filter that is used to the global search for regular expressions.
Syntax:
grep [options] pattern [files]
Question - 70 : - What is the tail command in Linux?
Answer - 70 : -
The Tail command print the last N number of lines of the given data, it prints 10 lines by default.
Syntax:
tail [OPTION]... [FILE]
Example:
$ cat names.txt
Tableau
sql server
linux administration
Now, check the syntax without giving any option or input.
$ tail state.txt