Setting up NFSv4 Shares on RHEL derivatives on Amazon EC2 Cloud

It’s easy and straightforward. This post shows how to share a nfs mount point across the network.

On the server and client: ensure the following packages are installed: nfs-utils, nfs-utils-lib and portmap.

Server setup:

1. edit the exports file

vim /etc/exports

2. add the following line to the exports file. ( note: this step assumes that you have a directory /buckets and you want to allow everyone in the network be able to connect and use. The /buckets directory is owned by “nobody” user. )

/buckets *(rw,sync,no_root_squash,no_subtree_check,fsid=0)

3. run exportfs and mount the mount points

exportfs -ar

3. start the services portmap and nfs.

service start portmap; service start nfs

4. verify the exports, by running exportfs in verbose mode

exportfs -v

Client Setup:

1. start portmap service

service start portmap

2. mount the nfs share. ( optional: add to /etc/fstab entry )

mount -t nfs4 ip_addr_of_nfs_server:/ ./test/

Firewall setup:

Ensure that TCP Ports: 111 and 2049., UDP Ports: 111 and 2049 are open between the NFS server and client(s).

In case of Amazon EC2, this can be configured in “EC2 SecurityGroups”. For simple cases, assuming all the instances are under the same security group, the source should be same as the security group under which all the instances run. And within instances, the private IP/DNS entry of the instances can be used to access the NFS server.

compiling OpenOffice 3.3 in RHEL 5 Derivatives

In one of the projects, I was tasked with the activity of packaging openoffice 3.3.0 with a custom watermarking patch for EL5 based platforms.

There was no sane build time dependency list documented. Hence, on a trial and error basis, I was able to compile a list which helped me build OOo.

The above steps were documented on gist – 1269805.

enabling 64 bit kernel in OSX Snow Leopard

As my Mac got upgraded to 8 GiB RAM, certain apps like VirtualBox was not able to use more than 4 GiB RAM.The obvious solution was to enable 64 bit kernel. Of-course the downside is, you’ll end up recompiling certain pieces of sofware.

sudo systemsetup -setkernelbootarchitecture x86_64

CentOS 6 Net Install URLs

Like the earlier versions, CentOS 6 allows network installation thru’ Internet. Quite useful, if you don’t have time for downloading the full ISOs or if your media becomes corrupt or if you have very fast internet connection.

Most of the CentOS mirrors provide the necessary images. I have quoted the original centos mirror and my preferred mirror.

For 32 bit:

For 64 bit:

Thats it folks! The installer will download whatever is needed.

what does “rc” in .bashrc stand for?

Link: what does “rc” in .bashrc stand for?


Steven explains:

As is often the case with obscure terms, the Jargon File has an answer:

[Unix: from runcom files on the CTSS system 1962-63, via the startup script /etc/rc] Script file containing startup instructions for an application program (or an entire operating system), usually a text file containing commands of the sort that might have been invoked manually once the system was running but are to be executed automatically each time the system starts up.

Thus, it would seem that the “rc” part stands for “runcom”, which I believe can be expanded to “run commands”. In fact, this is exactly what the file contains, commands that bash should run.