We are down to questions that are definitely appropriate for the list.
"Jeffrey B. Layton" laytonjb@bellsouth.net writes:
Eric W Biederman wrote:
"Jeffrey B. Layton" laytonjb@bellsouth.net writes:
Could you list some pros and cons for a prospective customer that is thinking about switching to LinuxBIOS but they are used to the regular old BIOS?
The quick list.
Pros: Better serial console support. Better debuggability. Better manageability. (You can do everything under Linux) Quick boot times. Has been tested on big (1000 node) clusters. Vendors care about cluster issues. You get the source.
Cons: Boots differently. Harder to find people supporting it.
I've got a question about the serial console support and the better manageability. With LinuxBIOS can you put BIOS messages across the network to the master node from power on? Or do you have to wait until you get to Lilo (and then use something like netconsole in the kernel)?
You can do serial from power on. Over the network is a more interesting problem, and hasn't been fully solved yet. Currently I connect the serial port to a box with a lot of serial ports, and that box is network accessible.
NIC hardware is noticeably more complex than serial ports so getting a network console going from power on is still an open issue. I don't know that it has been tested much yet.
As for the manageability issue. How is the cluster more manageable with LinuxBIOS (I'm not being argumentative, but rather curious)?
For example, if I have a cluster that's pretty stable where I don't lose many nodes and I don't need to change the BIOS at all, then what does LinuxBIOS give me in terms of manageability?
Manageability is really about when things fail, and have problems, not when they work. But even when things are mostly working you can set your BIOS options the very first time from Linux, and trust they are getting set the same as every other node. You get a reliable network boot, with etherboot. You get a fast boot. You get messages over the serial console from power on.
Maybe some of these things are only really annoying when the don't exist and you have lots of hardware. For me I like the ability to do a full install including flashing the BIOS on 350 nodes in under 10 minutes.
But manageability comes down to the fact that the little things are getting fixed in LinuxBIOS so it is not a pain to work with, after the learning curve.
Eric