[ENBD] ENBD with 2.4.2-kernel

[Adrian Turcu]

Hello again,

I have a strange problem here:
 - when I tried to lunch nbd-server and nbd-client on the same
machine and make something with /dev/nda , like mkfs.ext2 -c /dev/nda or
something else, well, the utility is freezing and I will get a lot of errors in
the server side. Here are what I do and after the error.

-server (node1)
  nbd-server 4017 /dev/sdb -i "NBDabcdefNBD" -b 1024

-client (node2)
  insmod -f /tmp/nbd.o show_errs=1 rahead=20 merge_requests=0 sync_intvl=10
  nbd-client localhost 4017 localhost -b 1024 -t 5 /dev/nda

and after a mkfs.ext2 -c /dev/nda or raidstart /dev/md0 (which include the nda device)
I'll get this in the log file (nbd-server file):

nbd-server: server (-1) opened port #4017 on socket 1
nbd-server: server (-1) read passwd ok
nbd-server: server (-1) got cliserv magic ok
nbd-server: server (-1) sent size 3784310784 ok
nbd-server: server (-1) sent sig ok
nbd-server: server (-1) suggested ro flags 0 ok
nbd-server: server (-1) received blksize 1024 ok
nbd-server: server (-1) sent/negotiated blksize 1024 ok
nbd-server: server (-1) received pulse_intvl 10 ok
nbd-server: server (-1) sent/negotiated pulse interval 10 ok
nbd-server: server (-1) agreed 1 channels ok
nbd-server: server (-1) selected free port at 4018
nbd-server: server (-1) posted port 4018 ok
nbd-server: server (-1) manager started new process group 1008
nbd-server: server (-1) manager set CHLD USR1 USR2 HUP TERM signal handlers
nbd-server: server (0) opened port #4018 on socket 5
file: Can not seek locally to offset 2147500032!
nbd-client-server: writenet exits FAIL
file: Can not seek locally to offset 2147501056!
nbd-client-server: writenet exits FAIL
file: Can not seek locally to offset 2147502080!
...
file: Can not seek locally to offset 3623884800!
nbd-client-server: writenet exits FAIL
file: Can not seek locally to offset 3623885824!
nbd-client-server: writenet exits FAIL

The client, after has established the connection looks like

nbd-client: client (-1) starts introduction sequence on port 4017
nbd-client: client (-1) got session port 4018 ok
nbd-client: client (-1) introduction sequence ends ok
nbd-client: client (0) begins main loop
nbd-client-netserver: client (0) short read from net to buffer  offset 0, wanted 4096 got -110
nbd-client-netserver: net_recv_reply exits INVAL for req type 0 with handle 0x0 len 4096 offset 3784245248
nbd-client-server: readnet exits FAIL
nbd-client: Read_stat (0) failed Timer expired port 4018 so clr sock
nbd-client: manager sighandler received signal 17
nbd-client: sighandler relaunches child from manager 
nbd-client: client (-1) main childminder checking pid 1084

Device a:       Open 
[a] State:      verify, rw, enabled, show_errs, sync, last error 0
[a] Queued:     +0R/0W curr reqs =0R/0W real reqs +0R/0W max reqs
[a] Buffersize: 86016   (sectors=168)
[a] Blocksize:  1024    (log=10)
[a] Size:       3695616KB
[a] Blocks:     3695616
[a] Sockets:    1       (*)
[a] Requested:  0       (0)     0R/0W
[a] Despatched: 0       (0)     0R/0W
[a] Errored:    0       (0)     0+0
[a] Pending:    0       (0)     0R/0W+0R/0W
[a] Kthreads:   0       (0 waiting/0 running/0 max)
[a] Cthreads:   1       (+)
[a] Cpids:      1       (1084)


and then, on the error phase, I can see the "Sockets" like:

[a] Sockets:    1       (.)


By the way, everythings are ending with a core file where
I could saw a line like this one:

nbd-cache/bitmap: client test of bitmap FAILED on mmaped NBD journal file for %d bytes from 0x%x

and more (I don't know any utility to decrypt this file, and probably is not relevant for you
this line)

Well, for my configuration it's vital to have the client and server running
on the same machine at a time. If the server is running on a machine and
the client is running on another one, things looks fine, I meen no errors until now.

I'm using 2.4.2 kernel and nbd-2.4.21 on RedHat.

Please, help me.

Thank you in advance,

-- 
Adrian Turcu
System Administrator