[syslinux] RE: VFS: Cannot open root device, pxelinux nfsroot

[rob.vogel at hetnet.nl]

Thank's Josef and Martijn,


>usually you should see something like
>IP-Config [dhcp answer]               
>NET4:[..]
>Looking up port of RPC 10003/2 on [server IP]
>Looking up port of RPC 10005/1 on [server IP]
>VFS: Mounted root (nfs filesystem)

I don't see that, but there are no errors about portmap or rpc either.
rpcinfo finds portmapper, mountd, nfs runnig.

>Are you sure you have nfsroot in the kernel? Does the client get some IP address
>in the kernel? Is the network card in the kernel (*fixed, not as a module!*)?
Yes, I got Networking Options:
TCP/IP networking (CONFIG_INET), IP: kernel level autoconfiguration (CONFIG_IP_PNP),
IP: DHCP support (CONFIG_IP_PNP_DHCP)
File Systems:
/dev file system support (CONFIG_DEVFS_FS), Automatically mount at boot (CONFIG_DEVFS_MOUNT)
Network File Systems:
NFS file system support (CONFIG_NFS_FS), Root file system on NFS (CONFIG_ROOT_NFS)
So that should cover it all.

> on the machine where you are compiling the kernel, make /dev/nfs:
> mknod /dev/nfs c 0 255
> rdev <kernelimage> /dev/nfs

I did this ( I saw later it is not required, but) and now I get a differen error:

	Sim 710: no NCR53C710 adapter found
	request_module[scsi_hostadapter]: root fs not mounted
	NET4: linux TCP/IP 1.0 for NET4.0
	IP Protocols: ICMP,UDP,TCP,IGMP
	IP: Routing cache bash table of 2048 buckets, 16Kbytes
	TCP: Hash tables configured 
	NET4: Unix domain sockets 1.0/SMP for linux NET4.0
	Root-NFS: no nfs server available, giving up
	VFS: Unable to mount fs via NFS, trying floppy

At least it tries to mount via NFS, but now it sees no NFS daemon?
portmap, rpc.nfsd are running. rpcinfo -p netserver sees portmap,mountd and nfs.
Ifconfig sees eth0 with 192.168.1.1 

>> you don't want to use rdev.
> why not? (just curious, since I almost copy/paste'd this from the NFSROOT
> HOWTO).

I think 'rdev <kernelimage> /dev/nfs' is only used as default, if you don't override it with the kernel option: 
	'nfsroot=<ip-address>:</root/path>' 
it uses a default path, with rdev you override this option (and more if you wish). So it should be possible to leave 'root=/dev/nfs' out and use rdev instead.

/tftpboot/pxelinux.cfg/default I got:
LABEL  linux
KERNEL  bzImage
APPEND root=/dev/nfs ip=dhcp nfsroot=192.168.1.1:/netboot/base

I know nothing about tcpdump, but maybe who does can see something in it?
With tcpdump I get the following:

netserver:~ # tcpdump -ql > dat & tail -f dat[5] 
1)---------
1644tcpdump: listening on eth0 16:53:36.766368 0.0.0.0.bootpc > 255.255.255.255.bootps:  udp 548 16:53:36.766982 netserver.bootps > 255.255.255.255.bootpc:  udp 322 [tos 0x10] 16:53:36.766368 0.0.0.0.bootpc > 255.255.255.255.bootps:  xid:0x8ca0735a secs:1024 flags:0x8000 [|bootp]
2)---After this it says the following a few hundred times-- 
16:51:12.054549 netserver.32771 > 192.168.1.149.56074:  udp 516 (DF)16:51:12.054999 192.168.1.149.56074 > netserver.32771:  udp 4
arp who-has 192.168.
3)-------As last it says:
arp who-has 192.168.1.149 tell netserver

I hope someone can actually read this.
I don't have arp and bootp configured in the kernel, since I don't need it for nfs mount, right?

Anyone got a clue?
Thanks,

Rob