If you have multiple linux kernels with differents options in the command line in your bootloader (grub, lilo or other) and you wonder which one was used to boot, you can find out by looking in /proc/cmdline. Ex :
[root@picolo:~]# cat /proc/cmdline
ro root=LABEL=/
[root@picolo:~]#

I barely knew the guy but the news that he passed away is all around the blogoshpere. If you have 76 minutes to spare, have a look at his Last Lecture at the Carnegie Mellon University, it’s really worth it (I won’t comment on it since it is already widely commented everywhere else). Man, I wish I had this kind of teacher; he seemed to have been the kind of life changing one !

To know what directories are exported by a NFS server, you can use the showmount -e nfs_server from a NFS client.

[root@client:~]# showmount -e server
Export list for server:
/data/dir1 (everyone)
/data/dir2 client1 client2 client3

(The /data/dir2 is exported only to specified clients)

This is nothing new, but just in case you missed it, Yahoo! published a fairly detailed report about how to speed up your website response times : Best Practices for Speeding Up Your Web Site.

Many of the tips are common sense, some are somehow unexpected, and some I didn’t know like the HTTP/1.1 header ETAG. Let’s see what that’s about.

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If you’ve been following my blog for a while, you might have seen posts about SSH, RSYNC, ZFS Snapshots and so on. This article aims at describing the big picture, and to explain how I’ve been using those tools and technologies to build my own home backup system.

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