Dear David, "This is not relevant to any bug with any of the commands but just a clarification" I'm an amateur to the linux environment. I have been trying some days to find the serial number of linux operating system in a generic way(applicable to most of the distros). But I could not. I have tried the following possibilities. 1. Uname -X = is not supported in my machine, I hope I require an advanced version for this. 2. dmidecode does not have OS specific information. With this tool, serial numbers of BIOS, processor etc are successful but not that of OS'. 3. Cat /etc/*release or /etc/*version or cat /proc/version. 4. lsattr and sysinfo commands. Just for your info-I'm using RHEL 5.4 32 bit version. Is this serial number retrieval specific to vendor or not? Please help me in identifying the way to find the serial number of OS. Also let me know the difference between the version and release of a kernel. Uname -r gives me the release of the kernel and uname -v gives the version which I find actually as a date and time information - does it mean the build time of the kernel. Then what does cat /etc/*release file convey? I mean I want to what a version exactly mean and is it same as 5.4? Thanks, Sudarshan.