40
NE2552E Application Guide for ENOS 8.4
SYSLOG Server
During
switch
startup,
if
the
switch
fails
to
get
the
configuration
file,
a
message
can
be
recorded
in
the
SYSLOG
server.
The
NE2552E
supports
requesting
of
a
SYSLOG
server
IP
address
from
the
DHCP
server
as
described
in
RFC
2132,
option
7.
DHCP
SYSLOG
server
request
option
is
enabled
by
default.
Manually
configured
SYSLOG
server
takes
priority
over
DHCP
SYSLOG
server.
Up
to
two
SYSLOG
server
addresses
received
from
the
DHCP
server
can
be
used.
The
SYSLOG
server
can
be
learnt
over
a
management
port
or
a
data
port.
Use
the
show logging
command
to
view
the
SYSLOG
server
address.
DHCP
SYSLOG
server
address
option
can
be
enabled/disabled
using
the
following
command:
DHCP Snooping
DHCP
snooping
provides
security
by
filtering
untrusted
DHCP
packets
and
by
building
and
maintaining
a
DHCP
snooping
binding
table.
An
untrusted
interface
is
a
port
that
is
configured
to
receive
packets
from
outside
the
network
or
firewall.
A
trusted
interface
receives
packets
only
from
within
the
network.
By
default,
all
DHCP
ports
are
untrusted.
The
DHCP
snooping
binding
table
contains
the
MAC
address,
IP
address,
lease
time,
binding
type,
VLAN
number,
and
port
number
that
correspond
to
the
local
untrusted
interface
on
the
switch;
it
does
not
contain
information
regarding
hosts
interconnected
with
a
trusted
interface.
By
default,
DHCP
snooping
is
disabled
on
all
VLANs.
You
can
enable
DHCP
snooping
on
one
or
more
VLANs.
You
must
enable
DHCP
snooping
globally.
To
enable
this
feature,
enter
the
following
commands:
Note:
When
you
make
a
DHCP
release
from
a
client,
the
switch
does
not
forward
the
Unicast
DHCP
release
packet
to
the
server,
the
entry
is
not
removed
from
the
DHCP
snooping
binding
table,
and
the
counter
for
Received
Request
packets
does
not
increase
even
though
the
release
packet
does
arrive
at
the
switch.
If
you
want
the
DHCP
Renew/Release
packet
to
be
forwarded
to
the
server
and
the
corresponding
entry
removed
from
the
DHCP
snooping
binding
table,
configure
an
interface
IP
address
with
the
sam
subnet
in
the
same
VLAN.
NE2552E(config)#
[no]
system dhcp syslog
NE2552E(config)#
ip dhcp snooping vlan
<vlan
number(s)>
NE2552E(config)#
ip dhcp snooping
Summary of Contents for ThinkSystem NE2552E
Page 27: ... Copyright Lenovo 2018 27 Part 1 Getting Started ...
Page 28: ...28 NE2552E Application Guide for ENOS 8 4 ...
Page 70: ...70 NE2552E Application Guide for ENOS 8 4 ...
Page 85: ... Copyright Lenovo 2018 85 Part 2 Securing the Switch ...
Page 86: ...86 NE2552E Application Guide for ENOS 8 4 ...
Page 112: ...112 NE2552E Application Guide for ENOS 8 4 ...
Page 134: ...134 NE2552E Application Guide for ENOS 8 4 ...
Page 154: ...154 NE2552E Application Guide for ENOS 8 4 ...
Page 194: ...194 NE2552E Application Guide for ENOS 8 4 ...
Page 218: ...218 NE2552E Application Guide for ENOS 8 4 ...
Page 234: ...234 NE2552E Application Guide for ENOS 8 4 ...
Page 238: ...238 NE2552E Application Guide for ENOS 8 4 ...
Page 239: ... Copyright Lenovo 2018 239 Part 4 Advanced Switching Features ...
Page 240: ...240 NE2552E Application Guide for ENOS 8 4 ...
Page 242: ...242 NE2552E Application Guide for ENOS 8 4 ...
Page 278: ...278 NE2552E Application Guide for ENOS 8 4 ...
Page 284: ...284 NE2552E Application Guide for ENOS 8 4 ...
Page 314: ...314 NE2552E Application Guide for ENOS 8 4 ...
Page 338: ...338 NE2552E Application Guide for ENOS 8 4 ...
Page 374: ...374 NE2552E Application Guide for ENOS 8 4 ...
Page 388: ...388 NE2552E Application Guide for ENOS 8 4 ...
Page 418: ...418 NE2552E Application Guide for ENOS 8 4 ...
Page 430: ...430 NE2552E Application Guide for ENOS 8 4 ...
Page 432: ...432 NE2552E Application Guide for ENOS 8 4 ...
Page 436: ...436 NE2552E Application Guide for ENOS 8 4 ...
Page 460: ...460 NE2552E Application Guide for ENOS 8 4 ...
Page 461: ... Copyright Lenovo 2018 461 Part 7 Network Management ...
Page 462: ...462 NE2552E Application Guide for ENOS 8 4 ...
Page 476: ...476 NE2552E Application Guide for ENOS 8 4 ...
Page 498: ...498 NE2552E Application Guide for ENOS 8 4 ...
Page 520: ...520 NE2552E Application Guide for ENOS 8 4 ...
Page 534: ...534 NE2552E Application Guide for ENOS 8 4 ...
Page 536: ...536 NE2552E Application Guide for ENOS 8 4 ...
Page 544: ...544 NE2552E Application Guide for ENOS 8 4 ...
Page 549: ... Copyright Lenovo 2018 549 Part 9 Appendices ...
Page 550: ...550 NE2552E Application Guide for ENOS 8 4 ...
Page 566: ...566 NE2552E Application Guide for ENOS 8 4 ...
Page 572: ...572 NE2552E Application Guide for ENOS 8 4 ...
Page 573: ......
Page 574: ...Part Number 01KN246 Printed in USA IP P N 01KN246 ...