Recursive Find and Replace in Directory

Sed to our rescue :)

1. Generating the file argument using "find" command :

find ./ -type f -exec sed -i 's/string1/string2/' {} \;

Finding Out The Linux Distro and Version Info

Lot's of times we end up working on a system/server we don't know any thing about. So to be able to do more meaningful stuff, we need to find out what breed of Horses we are actually gonna race with.

1. The most basic way to do it would be to use "/PROC/" file system.
More specifically, the "version" file.

bash# cat /proc/version
Linux version 2.6.9-42.ELsmp (bhcompile@hs20-bc1-1.build.redhat.com) (gcc version 3.4.6 20060404 (Red Hat 3.4.6-2)) #1 SMP Wed Jul 12 23:27:17 EDT 2006


2. Use "LSB" as fodder (Linux Standard Base)

bash# lsb_release -a
LSB Version: :core-3.0-ia32:core-3.0-noarch:graphics-3.0-ia32:graphics-3.0-noarch
Distributor ID: RedHatEnterpriseAS
Description: Red Hat Enterprise Linux AS release 4 (Nahant Update 4)
Release: 4
Codename: NahantUpdate4

Currently, most of the major Linux distros (UBUNTU, RED HAT, Free BSD etc) comply with the LSB.

3. A not so popular way (which might not work on some distros like Free BSD) would be

bash# cat /etc/*-release
Red Hat Enterprise Linux AS release 4 (Nahant Update 4)

4. Again, using /etc , we can get

bash# cat /etc/issue
Red Hat Enterprise Linux AS release 4 (Nahant Update 4)
Kernel \r on an \m

5. Using the boot up messages is another nifty way to get this info :

bash# dmesg | head -1
Linux version 2.6.9-42.ELsmp (bhcompile@hs20-bc1-1.build.redhat.com) (gcc version 3.4.6 20060404 (Red Hat 3.4.6-2)) #1 SMP Wed Jul 12 23:27:17 EDT 2006



Well, am sure that there might be many more ways to find this info, and if you do know of them, do leave a comment and let me know about it. Each day I realize that there is much more learn/know, that I get even more keen to dwell further into this beast of a Linux.

NFS Server Not Responding

Incase you are able to connect to the NFS server, and able to mount using , for example ,say :

mount -t nfs -o nolock 10.88.27.76:/home/jayant /mnt

And are further able to access the FS as well (able to view directories and files), but any attempt to try and execute or access any big file (like "insmod"ing a kernel object, or executing helloworld executable) results in the heinous "NFS server not responding" error,i.e., something like the following:

nfs: server 10.88.27.76 not responding, still trying

,then try to increase the rsize to the maximum permissible value (in my case, 8192 bytes)...This might help...So, instead of cmd1, try the following command to mount :

mount -t nfs -o nolock,rsize=8192 10.88.27.76:/home/jayant /mnt