Question : How files transfer could be slow and normal at the same time ?
Transfer initiated from : Windows 7 computer on VLAN computer
Source : NSD share (samba from IBM GPFS) on VLAN server
Destination : Windows 7 computer on VLAN computer (the one used to initialize)
Research Track : Suppose that this can be related to the host layer of the OSI model
I'm linux Sys Admin for many clients. I use remote login, and i have'nt the possibility to test everything.
One client get a strange behaviour : From a windows 7, by opening explorer.exe and transfering one file of 1Gb (zip, iso, data, created with dd command, etc ...) from a LAN share (see configuration below) using UNC path you can have 2 differents behaviors depending of the file.
A) You can have a slow transfer rate, 7-10 Mb/s
B) You can have a normal transfer rate, 50-70 Mb/s
This transfert rate is permanent for type of file. That mean, if you try from another time at different days and hours, you will get the same result. Each time, zip file or iso file have normal transfer rate. When data file, fake file created by dd, have low transfer rate.
From another computer with same or other windows version (windows 2012 server by example), same result.
If you try with another user account, same result.
If you mount the UNC path, same result.
With antivirus activated or not
I did tests and I observe this :
Transfer from another linux on another VLAN : transfer rate is 42 Mb/s for both type of file
Transfer with winscp from windows computer on another VLAN : transfer rate is 26 Mb/s for both type of file
Transfer with cygwin from windows computer on another VLAN using SCP (ssh) : transfer rate is 47-53 Mb/s for both type of file
Transfer with cygwin from windows computer on another VLAN using mount point : transfer rate is 7-10 Mb/s for A and 55 Mb/s for B
As client use wireshark and tell to me he observe this : Wireshark show that slow transfer A is done with SMB2 protocol and normal transfer B is done with NetBios/NBSS protocol
And because my tests show SCP (SSH) the transfer rate is normal (same for all files types) I oriented my search to the top protocols of the OSI model
But i know nothing about networking / protocole.
Could someone knowledgeable help me please ?
The share : It's an IBM Spectrum Scale (new GPFS name) shared by NSD server with NFS and SMB enable on a specific VLAN server
[root@nsd ~]# mmces service list
Enabled services: NFS SMB
NFS is running, SMB is running
# smbstatus -V
Samba version 4.6.16-gpfs-56
# testparm
Load smb config files from /var/mmfs/ces/smb.conf
rlimit_max: increasing rlimit_max (1024) to minimum Windows limit (16384)
Registered MSG_REQ_POOL_USAGE
Registered MSG_REQ_DMALLOC_MARK and LOG_CHANGED
Registered MSG_REQ_POOL_USAGE
Registered MSG_REQ_DMALLOC_MARK and LOG_CHANGED
Can't find include file /var/mmfs/ces/smb.conf.0.0.0.0
Can't find include file /var/mmfs/ces/smb.conf.internal.0.0.0.0
Processing section "[home]"
Loaded services file OK.
Server role: ROLE_DOMAIN_MEMBER
Press enter to see a dump of your service definitions
# Global parameters
[global]
netbios name = SPECSCALE
realm = xxxxxxxxxx.COM
server string = IBM NAS
workgroup = xxxxx
preferred master = No
ldap ssl = no
logging = syslog@0 file
max log size = 100000
add share command = /usr/lpp/mmfs/bin/mmcesmmccrexport
allow insecure wide links = Yes
change share command = /usr/lpp/mmfs/bin/mmcesmmcchexport
clustering = Yes
ctdb locktime warn threshold = 5000
delete share command = /usr/lpp/mmfs/bin/mmcesmmcdelexport
lock directory = /run/gpfs-samba/lock
log writeable files on exit = Yes
registry shares = Yes
smbd exit on ip drop = Yes
smbd profiling level = on
disable spoolss = Yes
printcap cache time = 0
disable netbios = Yes
server max protocol = SMB3_02
server min protocol = SMB2_02
unix extensions = No
auth methods = guest sam winbind
restrict anonymous = 2
security = ADS
max open files = 20000
socket options = TCP_NODELAY SO_KEEPALIVE TCP_KEEPCNT=4 TCP_KEEPIDLE=240 TCP_KEEPINTVL=15
include system krb5 conf = No
winbind max clients = 10000
winbind max domain connections = 5
winbind use default domain = Yes
gencache:stabilize_interval = 3600
winbind:request profile threshold = 10
idmap config sbm : range = 1000-500000
idmap config sbm : ldap_user_dn = cn=connect,ou=Special Users,dc=xxxxx,dc=local
idmap config sbm : ldap_url = ldap://master.local
idmap config sbm : ldap_server = stand-alone
idmap config sbm : bind_path_user = ou=People,dc=xxxxx,dc=local
idmap config sbm : bind_path_group = ou=Groups,dc=xxxxx,dc=local
idmap config sbm : backend = rfc2307
nfs4:acedup = merge
nfs4:chown = yes
nfs4:mode = simple
idmap config * : rangesize = 1000000
idmap config * : range = 10000000-299999999
idmap config * : read only = no
idmap:cache = no
shadow:sort = desc
shadow:snapdirseverywhere = yes
shadow:fixinodes = yes
shadow:snapdir = .snapshots
readdir_attr:aapl_max_access = false
fruit:veto_appledouble = no
fruit:nfs_aces = no
fruit:metadata = stream
fruit:copyfile = yes
gpfs:merge_writeappend = no
gpfs:winattr = yes
gpfs:hsm = yes
gpfs:prealloc = yes
gpfs:dfreequota = yes
gpfs:leases = yes
gpfs:sharemodes = yes
smbd:async search ask sharemode = yes
ctdb:smbxsrv_open_global.tdb = false
gencache:stabilize_count = 100000
time_audit:timeout = 5000
aio_pthread:aio open = yes
tdbsam:map builtin = no
winbind:online check timeout = 30
groupdb:backend = tdb
smbd:backgroundqueue = False
notify:inotify = yes
syncops:onmeta = no
fileid:fstype allow = gpfs
fileid:algorithm = fsname
dbwrap_tdb_mutexes:* = true
ctdb:registry.tdb = yes
idmap config * : backend = autorid
mangled names = illegal
map hidden = Yes
map system = Yes
store dos attributes = Yes
posix locking = No
dfree cache time = 100
include = /var/mmfs/ces/smb.conf.internal.0.0.0.0
durable handles = No
ea support = Yes
force unknown acl user = Yes
read only = No
aio read size = 1
aio write size = 1
strict allocate = Yes
vfs objects = shadow_copy2 syncops gpfs fileid time_audit
[home]
path = /gpfsxxxxx/home
wide links = Yes
smb encrypt = if_required
