[Nbd] Can not open NBD error

I compiled a nbd-2.8.6 on my redhat 9 with kernel 2.4.20.

Because the absent of INSTALL file in the nbd-2.8.6.tar.gz , I use the normal way to install the nbd on both

client side and server side. These commands are :

After do these, I use the following method to create server nbd service:

[root@...117... ramdisk]# ls -l /mnt/ramdisk/a
-rw-r--r--    1 root     root     63197184 4ÔÂ 15 23:38 /mnt/ramdisk/a
[root@...117... ramdisk]# nbd-server 2000 /mnt/ramdisk/a
[root@...117... ramdisk]# ps -aux | grep nbd-server
root      5775 0.0 0.1 1820 612 ?        S    Apr15   0:00 nbd-server 2000 /mnt/ramdisk/a
root     29534 0.0 0.1 4832 656 pts/0    S    16:15   0:00 grep nbd-server

Then in the client side,

[root@...118... sbin]# ls -l /dev/nb1
brw-rw---- 1 root disk 43, 1 2003-01-30 /dev/nb1

[root@...118... sbin]# nbd-client 192.168.0.15 2000 /dev/nb1

After done the above command, strange thing happened. There is nothing output. I do not know whether the client setup successfully. Then I do

[root@...118... sbin]# ps -aux | grep nbd-client
root 8842 0.0 0.1 4892 636 pts/0 S 02:13 0:00 grep nbd-client

I do not know why there are nothing output when the nbd-client not setup successfully.

[root@...118... nbd-2.8.6]# gdb --args nbd-client 192.168.0.15 2000 /dev/nb1

GNU gdb Red Hat Linux (5.3post-0.20021129.18rh)
Copyright 2003 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i386-redhat-linux-gnu"...

When gdb stop at the 211 line, i use the step way, and found

(gdb) p nbddev
$2 = 0xbfa6f911 "/dev/nb1"

It's normal.

211 nbd = open(nbddev, O_RDWR);

When 211 was executed, nbd return error.

(gdb) p nbd
$4 = -1208637784

212 if (nbd < 0)
213 err("Can not open NBD: %m");

To find the reason why nothing print out, I step into the err function. And We found that the program run into the line where use a ifdef clause:

#ifdef ISSERVER
syslog(LOG_ERR, "%s", s1);
#else

Is there something going wrong?
we tail the log, we found that,

[root@...118... log]# tail messages
Apr 15 10:50:28 gt13 nbd_client[7307]: Can not open NBD: Illegal seek
Apr 15 10:51:06 gt13 nbd_client[7390]: Can not open NBD: Illegal seek
Apr 16 02:06:21 gt13 nbd_client[8819]: Can not open NBD: Illegal seek
Apr 16 02:06:33 gt13 nbd_client[8822]: Can not open NBD: Illegal seek
Apr 16 02:09:06 gt13 nbd_client[8825]: Can not open NBD: Illegal seek
Apr 16 02:10:17 gt13 nbd_client[8837]: Can not open NBD: Illegal seek
Apr 16 02:23:10 gt13 nbd_client[10975]: Can not open NBD: No such device or address
Apr 16 02:28:59 gt13 nbd_client[10993]: Can not open NBD: No such device or address
Apr 16 02:35:45 gt13 nbd_client[11025]: Can not open NBD: No such device or address
Apr 16 02:36:03 gt13 nbd_client[11029]: Can not open NBD: No such device or address

So what's going on?