From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Childs Subject: Re: [PATCH] pypxeboot bootloader Date: Thu, 08 Feb 2007 14:27:40 +0000 Message-ID: <45CB335C.1090809@cs.tcd.ie> References: <45C7114E.10207@cs.tcd.ie> <20070205173612.GH5181@york.uk.xensource.com> Reply-To: Stephen.Childs@cs.tcd.ie Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20070205173612.GH5181@york.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Tim Deegan Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Tim Deegan wrote: > First impressions: this looks really useful but has a few rough edges > that need to be knocked off. (I haven't had a chance to try this on a > real machine yet.) I absolutely agree, this was the first working version and I was aware there were nasties in it. >> +for line in udhcplines: >> + s = line.strip() >> + f = s.split() >> + >> + if s[0]=='{' and s[-1]=='}': >> + dhcpinfo=eval(s, {"__builtins__" : {}}) >> + for k in dhcpinfo: >> + dhcpinfo[k]=dhcpinfo[k].strip() > > Executing the results of programs scares me. Could you just parse it? Yes quite. Sorry that was cut-and-paste code so I didn't think about it enough. Will rewrite. >> +ipaddr=dhcpinfo['ip'] >> +ipaddrlist=ipaddr.split('.') >> +hexip=commands.getstatusoutput("/usr/bin/gethostip -x "+ipaddr)[1] > This requires syslinux to be installed on the Xen host, and isn't > hard to do by hand: "%2.2x%2.2x%2.2x%2.2x" % tuple(map (int, ipaddrlist)) > (I'm sure more heavyweight python hackers can correct my style.) Yes of course I'll change that. >> +tmpdir="/var/lib/xen/" >> + >> +os.chdir(tmpdir) >> +commandstr="tftp -c get "+servaddr+":pxelinux.cfg/"+hexip >> +#print "running command "+commandstr >> +getpxeres=commands.getstatusoutput(commandstr) > > You'll need to be more careful with temporary file names -- here at > least the filename is unique to the guest (we hope!) but for the kernel > etc., two boots could clash. Also, you don't seem to remove the > downloaded config files. Yes that all needs tidying up. Unfortunately the version of tftp I was using didn't actually support "get " as advertised which I was initially going to use. I'll have to download to the filename supplied by the server then move to a tmpfile. On the subject of removing files yes of course I'll remove the config files. Comparing with pygrub, that seems to leave kernels and initrds clogging up /var/lib/xen, and I suppose I'll end up doing the same. I suppose you could set up tmpwatch to clean it up, but it still seems a bit messy. Expect a new patch soon ... Stephen -- Dr. Stephen Childs, Research Fellow, EGEE Project, phone: +353-1-8961797 Computer Architecture Group, email: Stephen.Childs @ cs.tcd.ie Trinity College Dublin, Ireland web: http://www.cs.tcd.ie/Stephen.Childs