what is stored in /proc ? what is significance of /proc in linux ?

NetApp,

what is stored at /lib/modules ?

NetApp,

What is atomic function / atomic variable ?

Broadcom,

if one of the critical section code (linked list) is under ISR & another one in kernel thread ? How you will synchronize for this critical section code ?

NetApp,

linux file defaults permition

How to create secured appeche web sever ?

HCL,

I would like to know whether Simado and Setu products are they EPBX or not ?

IBM,

What do fork() internally call?

What does exec family return?

diff b/w spinlock, seamaphores and mutex and where to use it.

Intel,

1.Diff between Active and passive FTP? 2.What is anacron? 3.Diff between yum update and yum install while doing for kernel? 4.root_squash and no_root_squash does what? 5.What are the commands will you execute to find a new hardware? 6.How will you find out a lun allocated from SAN? 7.What is the main diff in CaT5 and CAT6 cable, except the 1/100 and 1/1000? 8.What is stale NFS and How will you fix it? 9.What is kernel panic error? 10.How will you recover password and shadow file, in case both got deleted. Explain the steps? 11.Explain boot process 12.What is network bonding. Explain the steps? 13.What are the exit codes returned by FSCK? 14.What is LDOM? 15.Diff between block and character device?

Wipro,

1. Where the History file can be located? 2. How will you harden the server? 3. Diff between Raid 1 and Raid 5? 4. What is the largest disk size can be used in LVM? 5. How will you remove a PV from lvm without any data loss? 6. What is the diff between ext3 and ext2 File system? 7. How we can use resize2fs, what is the purpose? 8. What is the purpose of LVM? Why it is used? 9. If the FS is in read-only mode, so we cannot create any file. How will you fix it? 10. How to create swap partition after OS installation? 11. What is the diff between ssh and telnet? 12. How to find out the dependency required for a package?

IBM,

Port number is already in use .. how to fix for apache..?

Google,

What are system calls used for process management in linux?

Explain process management system calls in linux?