9-6
User
Guide
for
the
Cisco
Application
Networking
Manager
5.2
OL-26572-01
Chapte
r
9
Configuring
Stickiness
Sticky
Groups
Sticky
Groups
The
ACE
uses
the
concept
of
sticky
groups
to
configure
stickiness.
A
sticky
group
allows
you
to
specify
sticky
attributes.
After
you
configure
a
sticky
group
and
its
attributes,
you
associate
the
sticky
group
with
a
Layer
7
pol
icy-map
action
in
a
La
yer
7
ser
ver
load
balancing
(SLB)
policy
map.You
can
cr
eate
a
maximum
of
40
96
st
icky
gr
oups
in
each
context.
Each
st
icky
gr
oup
that
you
configure
on
t
he
ACE
contains
a
series
of
parameters
that
determine
the
following:
•
Sticky
method
•
Ti
m
e
o
u
t
•
Replication
•
Sticky
method-specific
attributes
Note
The
context
in
which
you
configure
a
sticky
group
must
be
associated
with
a
resource
class
that
allocates
a
portion
of
ACE
resources
to
stickiness.
See
the
“Using
Resource
Classes”
section
on
pa
ge
6-43
for
information
about
configuring
ACE
resources.
Related
Topics
•
Configuring
Stickiness,
page
9-1
•
Sticky
Types,
page
9-2
•
Sticky
Table,
page
9-6
Sticky
Table
The
ACE
uses
a
sticky
table
to
keep
track
of
sticky
connections.
Table
entries
are
as
follows:
•
Sticky
groups
•
Sticky
methods
•
Sticky
connections
•
Real
servers
The
sticky
table
can
hold
a
maximum
of
four
million
entries
(four
million
simultaneous
users).
When
the
table
reaches
the
maximum
number
of
entries,
additional
sticky
connections
cause
the
table
to
wrap
and
the
first
users
become
unstuck
from
their
respective
servers.
The
ACE
uses
a
configurable
timeout
mechanism
to
age
out
sticky
table
entries.
When
an
entry
times
out,
it
becomes
eligible
for
reuse.
High
connection
rates
may
cause
the
premature
aging
out
of
st
icky
entries.
In
this
case,
the
ACE
reuses
the
entries
that
are
closest
to
expiration
first.
Sticky
entries
can
be
either
dynamic
(generated
by
the
ACE
on
demand)
or
static
(user-configured).
When
you
create
a
static
sticky
entry,
the
ACE
places
the
entry
in
the
sticky
table
immediately.
Static
entries
remain
in
the
sticky
database
until
you
remove
them
from
the
configuration.
You
can
create
a
maximum
of
4096
static
sticky
entries
in
each
context.
If
the
ACE
takes
a
real
server
out
of
service
for
whatever
reason
(probe
failure,
no
inservice
command,
or
ARP
timeout),
the
ACE
removes
from
the
database
any
sticky
entries
that
are
related
to
that
server.
