The SDLC entity provides support for communication links. There is only one instance per node. For each physical line, SDLC creates a Link subentity, which manages all stations on the line. For each logical station, SDLC creates a Station subentity that is subordinate to the Link entity, which manages the station. For each enabled Station that establishes a connection, SDLC creates a Port entity.
1 – create
create sdlc The create verb generates a new instance of the SDLC entity or subentity. Create sets the entity state to off and sets the entity's attributes to their default values. There are no attributes for the create sdlc command. Ex, ncl> create sdlc
2 – delete
delete sdlc The delete sdlc command deletes the single SDLC instance. You cannot delete the SDLC entity while subentities (Links, Stations) exist. Ex, ncl> delete sdlc
3 – show
show sdlc The show sdlc command displays the attributes for communication lines or links. There is only one instance per node. Ex, ncl> show sdlc all counters
3.1 – Status
UID Displays the entity's unique identifier, which
is generated when the Peer Server creates the
entity.
Connections Displays the number of connections that are
currently active.
3.2 – Characteristics
Version Displays the version number of the SDLC software
that is executing.
3.3 – Counters
Creation The time that the SDLC entity was created. Time Resource The total number of resource allocation failures; Allocation for example, insufficient memory. Failures
4 – Link subentity
The SDLC Link subentity instance exists for each physical line and manages all stations on the line.
4.1 – create
create sdlc link
The create sdlc link command creates an instance of the SDLC Link
subentity for each physical line, which manages all stations on the
line. Creation also allocates resources for the subentity, and set
its characteristics to their default values.
Ex, ncl> create sdlc link sdlc-1 line modem connect line line-0, -
_ncl> capability primary
4.1.1 – Characteristics
Line local entity Specifies the Modem Connect Line on
name which the SDLC protocol operates.
For more information about Modem
Connect Line refer to the
DECnet-Plus Network Control
Language Reference.
Capability primary | Specifies the capability of the
secondary | Station subentities of this Link
negotiable entity. Negotiable stations can
become either primary or secondary.
The default is negotiable.
Configuration pointtopoint | Specifies whether the Link supports
multipoint only a point-to-point connection or
can also support a multipoint
connection. Multipoint supports one
or more than one connection. The
default is pointtopoint. The Peer
Server does not support multipoint
primary connections.
Connection nonswitched | Specifies whether the Link supports
Type switched switched or nonswitched connections.
The default is nonswitched.
Receive (1-32764) Specifies the maximum frame size
Frame Size (excluding the header) that can be
received on the line represented by
this Link. The default is 1000.
Reply Timer (100-60000) Specifies the time (in milliseconds)
to wait for an acknowledgment before
starting the recovery procedure. The
default is 3000.
Retry (0-128) Specifies that, when the Link is
Maximum secondary, this is the maximum
number of times a frame is
retransmitted before assuming a
fatal error. When the Link is
primary, this is the number of times
that a retry will be attempted. The
default is 15.
Poll Pause (0-60000) The time in milliseconds to pause
when the end of the polling list is
reached. Used only when the Link is
primary. The default is 200.
Service (1-255) Specifies the maximum number of
Limit regular scans of the service order
table for secondary Stations that
will be made before a special scan
is made. Used when the Link is
multipoint primary. The default is
4. Not used at this time.
TWA Send no | yes Specifies whether the Link provides
Priority priority for outbound services when
configured for Two-Way Alternating
(half-duplex) data transfer in the
multipoint primary mode. Yes
means that PIUs that arrive for
transmission while data is being re-
ceived are transmitted immediately.
No, the default, means that outbound
transmission is strictly determined
by the position of station service
order entries in the Service Order
Table. This attribute is not
relevant to SDLC point-to-point
operations. Not used at this time.
4.2 – delete
delete sdlc link The delete sdlc link command deletes an instance of the SDLC Link subentity and deallocates resources for the subentity. The Link subentity must be in the off state and must have no Station subentities. Ex, ncl> delete sdlc link sdlc-0
4.3 – disable
disable sdlc link The disable sdlc link command disables an instance of the SDLC Link subentity. You can only disable a previously enabled entity. The disable command stops the operation of the Link subentity. To be successful with this command, all Station subentities on the Link must have been disabled. At the completion of the command the subentity is off. Ex, ncl> disable sdlc link sdlc-0
4.4 – enable
enable sdlc link The enable sdlc link command places the SDLC Link subentity in its enabled state (on). An association may be made between the Link subentity and the Modem Connect Line entity of the physical line on which the protocol operates. For more information about Modem Connect Line refer to the DECnet-Plus Network Control Language Reference. Ex, ncl> enable sdlc link sdlc-0
4.5 – set
set sdlc link The set sdlc link command let you set the attributes for the SDLC Link subentity. The SDLC Link subentity defines the data link attributes that are shared by its Station subentities. Ex, ncl> set sdlc link sdlc-0 capability = primary
4.5.1 – Characteristics
Line local entity Specifies the Modem Connect Line on
name which the SDLC protocol operates.
This attribute is settable only
when the Link is disabled. For
more information about Modem
Connect Line refer to the
DECnet-Plus Network Control Language
Reference.
Capability primary | Specifies the capability of the
secondary | Station subentities of this Link
negotiable entity. Negotiable stations can
become either primary or secondary.
This attribute is settable only when
the Link is disabled. The default is
negotiable.
Configuration pointtopoint | Specifies whether the Link supports
multipoint only a point-to-point connection or
can also support a multipoint
connection. Multipoint supports one
or more than one connection. This
attribute is settable only when the
Link is disabled. The default is
pointtopoint. The Peer Server does
not support multipoint primary
connections.
Connection nonswitched | Specifies whether the Link supports
Type switched switched or nonswitched connections.
This attribute is settable only when
the Link is disabled. The default is
nonswitched.
Receive (1-32764) Specifies the maximum frame size
Frame (excluding the header) that can be
Size received on the line represented by
this Link. This attribute is settable
only when the Link is disabled. The
default is 1000.
Reply Timer (100-60000) Specifies the time (in milliseconds)
to wait for an acknowledgment before
starting the recovery procedure. The
default is 3000.
Retry (0-128) Specifies that, when the Link is
Maximum secondary, this is the maximum
number of times a frame is
retransmitted before assuming a
fatal error. When the Link is
primary, this is the number of times
that a retry will be tried. This
attribute is settable only when the
Link is disabled. The default is 15.
Poll Pause (0-60000) The time in milliseconds to pause
when the end of the polling list is
reached. Used only when the Link is
primary. The default is 200.
Service (1-255) Specifies the maximum number of
Limit regular scans of the Service Order
Table for secondary Stations that
will be made before a special scan
is made. Used when the Link is
primary. Is settable only when the
Link is disabled. The default is 4.
Not used at this time.
TWA Send no | yes Specifies whether the Link provides
Priority priority for outbound services when
configured for Two-Way Alternating
(half-duplex) data transfer in the
multipoint primary mode. Yes
means that PIUs that arrive for
transmission while data is being
received are transmitted immediately.
No, the default, means that outbound
transmission is strictly determined
by the position of station service
order entries in the service order
table.
This attribute is not relevant to
SDLC point-to-point operations. This
attribute is settable only when the
Link is disabled. Not used at this
time.
4.6 – show
show sdlc link The show sdlc link command displays the values of the attributes for the SDLC Link subentity. The SDLC Link subentity defines the data link attributes that are shared by its Station subentities. Ex, ncl> show sdlc link sdlc-0 all status
4.6.1 – Identifier
Name A Simplename that is unique among the SDLC Link
entities maintained by the SDLC module. The network
manager specifies Name when the Link is created.
4.6.2 – Status
UID Displays the entity's unique identifier, which is
generated when the the entity is created.
State Displays the operational state of this SDLC Link
subentity. Possible states are
Inoperable The Link cannot be enabled.
Off You have issued a disable command for
this Link. The Link is in the
inactive or pending inactive state.
On You have issued an enable command for
this Link.
Role Displays the role this Link has taken. Values for
Role are:
Idle No role has been assumed yet.
Primary The role is that of a primary Link.
Secondary The role is that of a secondary Link.
4.6.3 – Characteristics
Line local entity Displays the Modem Connect Line on
name which the SDLC protocol operates.
You must specify a value in
order to enable the link. For more
information about Modem Connect
Line refer to the DECnet-Plus
Network Control Language Reference.
Capability primary | Displays the capability of the
secondary | Station subentities of this Link
negotiable entity. Negotiable stations can
become either primary or secondary.
The default is negotiable.
Configuration pointtopoint | Displays whether the Link supports
multipoint only a point-to-point connection or
can also support a multipoint
connection. Multipoint supports one
or more than one connection. The
default is pointtopoint. The Peer
Server does not support multipoint
primary connections.
Connection nonswitched | Displays whether the Link supports
Type switched switched or nonswitched connections.
The default is nonswitched.
Receive (1-32764) Displays the maximum frame size
Frame (excluding the header) that can be
Size received on the line represented by
this Link. The default is 1000.
Reply Timer (100-60000) Displays the time (in milliseconds)
to wait for an acknowledgment before
starting the recovery procedure. The
default is 3000.
Retry (0-128) Displays that, when the Link is
Maximum secondary, this is the maximum
number of times a frame is
retransmitted before assuming a
fatal error. When the Link is
primary, this is the number of times
that a retry will be tried. The
default is 15.
Poll Pause (0-60000) Displays the time in milliseconds to
pause when the end of the polling
list is reached. Used only when the
link is primary. The default is 200.
Service (1-255) Displays the maximum number of
Limit regular scans of the Service Order
Table for secondary Stations that
will be made before a special scan
is made. Used when the Link is
primary. The default is 4. Not
used at this time.
TWA Send no | yes Displays whether the Link provides
Priority priority for outbound services when
configured for Two-Way Alternating
(half-duplex) data transfer in the
multipoint primary mode. Yes
means that PIUs that arrive for
transmission while data is being
received are transmitted immediately.
No, the default, means that outbound
transmission is strictly determined
by the position of station service
order entries in the service order
table.
This attribute is not relevant to
SDLC point-to-point operations. Not
used at this time.
4.6.4 – Counters
Group Polls The number of unnumbered group polls received on
this link.
Frame Receive The number of times the physical layer encountered
Errors an error trying to receive a frame.
Underlying The number of times the Link's underlying Line was
Lines deleted after the Link had established a connection
Deleted to it.
Creation Time The time that the SDLC Link subentity was created.
5 – Link Station Subentity
For each logical station on a line, SDLC creates a Station subentity that is subordinate to the Link entity, which manages the station.
5.1 – create
create sdlc link station The create sdlc link station command creates an instance of the Station subentity of the SDLC Link entity for each logical station on a line and allocates resources for the subentity. The create command sets the characteristic attributes to their default values. Ex, ncl> create sdlc link sdlc-0 station stn-0 address = c2
5.1.1 – Characteristics
Address 2 characters Specifies the address defined for
hexadecimal the secondary Station. The default
is 40.
Group 2 characters Specifies the group poll address for
Address hexadecimal this Station. A value of 0 indicates
that the Station is not in a group.
The default value is 0.
Transfer twa | tws Specifies the link level transmit/-
Mode receive capability of the Station.
The default is twa. TWA is Two Way
Alternate; TWS is Two Way
Simultaneous.
Modulo normal | Specifies that the Station supports
extended normal response mode (window size
ranges from 1 to 7) or normal
response mode extended (window
size ranges from 1 to 127). This
attribute is ignored for connections
that perform XID3 negotiation. The
default is normal.
Window Size (1-127) Specifies the maximum number of
received I-frames that may be
outstanding before this station
requires an acknowledgment response.
This value allows for the detection
of erroneous sequence numbers in
received frames. The default is 7.
Send Frame (1-32764) Specifies the maximum frame size
Size (excluding the header) this Station
can send. This value may be reduced
during preconnection XID
negotiation or by the Station's
client. The default is 265.
Inactivity (0-7200) Specifies the time (in seconds) to
Timer wait for a command before initiating
recovery action. This is used when
the Link is secondary. The default
is 30.
Pass Limit (1-254) Specifies the maximum number of
BLUs that can be sent to the second-
ary Station before starting data
transmission to the next Station in
the Link Service Order Table. This is
used when the Link is primary. The
default is 1. Not used at this time.
Select (1-60000) Specifies the time (in milliseconds)
Pause to pause before sending a response
with the final bit set. This is used
when the Link is secondary. The
default is 50.
Retry (0-255) Specifies the time (in seconds) to
Sequence pause after completing a retry
Pause sequence before beginning a new retry
sequence. This is used when the
Link is primary. The default is 0.
Not used at this time.
Retry (0-127) Specifies the maximum number of
Sequence retry sequences allowed. This is
Limit used when the Link is primary. The
default is 0. Not used at this time.
Immediate no | yes Specifies whether a Station
Poll subentity will be repolled when there
Retry is a reply time-out before proceeding
to next Station on the Link's Service
Order Table. The default is no. Not
used at this time.
5.2 – delete
delete sdlc link station The delete sdlc link station command deletes the Station subentity. The Station subentity must be in the off state before it can be deleted. Ex, ncl> delete sdlc link sdlc-0 station stn-0
5.3 – disable
disable sdlc link station The disable sdlc link station command stops the operation of the Station subentity of the Link. If a connection exists, the disable command halts protocol operation. When execution of the command completes the Station entity enters the off entity state. Ex, ncl> disable sdlc link sdlc-0 station stn-0
5.4 – enable
enable sdlc link station The enable sdlc link station command enables the Station for use. You must enable the link to be successful with this command. An association may be made between the Link subentity and the Modem Connect Line entity of the physical line on which the protocol operates. An enabled Station can accept incoming connection requests or initiate outgoing connection requests. For more information about Modem Connect Line refer to the DECnet-Plus Network Control Language Reference. Ex, ncl> enable sdlc link sdlc-0 station stn-0
5.5 – set
set sdlc link station The set sdlc link station command let you set the attributes for SDLC Link Station subentity. The SDLC Station subentity contains the data link attributes that are configured for this connection. Ex, ncl> set sdlc link sdlc-0 station stn-0 address = 62
5.5.1 – Characteristics
Address 2 characters Specifies the address defined for the
hexadecimal secondary Station. You can set this
attribute only when the Station is
disabled. The default is 40.
Group 2 characters Specifies the group poll address
Address hexadecimal for this Station. A value of 0
indicates that the Station is not in
a group. The default value is 0.
Transfer twa | tws Specifies the link level transmit/-
Mode receive capability of the Station.
The default is twa. TWA is Two Way
Alternate; TWS is Two Way
Simultaneous. This attribute is
settable only when the Station is
disabled.
Modulo normal | Specifies that the Station supports
extended normal response mode (window size
ranges from 1 to 7) or normal
response mode extended (window
size ranges from 1 to 127). This
attribute is ignored for connections
that perform XID3 negotiation. The
default is normal. This attribute is
settable only when the Station is
disabled.
Window Size (1-127) Specifies the maximum number of
received I-frames that may be
outstanding before this station
requires an acknowledgment response.
This value allows for the detection
of erroneous sequence numbers in
received frames. This attribute is
settable only when the Station is
disabled. The default is 7.
Send Frame (1-32764) Specifies the maximum frame size
Size (excluding the header) this Station
can send. This value may be reduced
during pre-connection XID
negotiation or by the Station's
client. This attribute is settable
only when the Station is disabled.
The default is 265.
Inactivity (0-7200) Specifies the time (in seconds) to
Timer wait for a command before initiating
recovery action. This is used when
the Link is secondary. The default is
30. This attribute is settable only
when the Station is disabled.
Pass Limit (1-254) Specifies the maximum number of
BLUs that can be sent to the second-
ary Station before starting data
transmission to the next Station in
the Link service order table. This is
used when the Link is primary. The
default is 1. This attribute is
settable only when the Station is
disabled. Not used at this time.
Select (1-60000) Specifies the time (in milliseconds)
Pause to pause before sending a response
with the final bit set. This is used
when the Link is secondary. The
default is 50.
Retry (0-255) Specifies the time (in seconds) to
Sequence pause after completing a retry
Pause sequence before beginning a new retry
sequence. This is used when the
Link is primary. The default is 0.
Not used at this time.
Retry (0-127) Specifies the maximum number of
Sequence retry sequences allowed. This is used
Limit when the Link is primary. The default
is 0. This attribute is settable only
when the Station is disabled. Not
used at this time.
Immediate no | yes Specifies whether a Station subentity
Poll will be repolled when there is a
Retry reply time-out before proceeding to
the next Station on the Link's
service order table. This attribute
is settable only when the Station is
disabled. The default is no. Not
used at this time.
5.6 – show
show sdlc link station The show sdlc link station command displays the values of the attributes for the SDLC Link entity's Station subentity. The SDLC Station subentity contains the data link attributes that are configured for this connection. Ex, ncl> show sdlc link sdlc-0 station stn-0 address, protocol state
5.6.1 – Identifier
Name Displays the unique name assigned to the Station
subentity by the network manager when the Station
is created.
5.6.2 – Status
UID Displays the entity's unique identifier, which is
generated when the Peer Server creates the entity.
State Displays the operational state of the Station
subentity. Setting the state is a result of
execution of the enable/disable commands.
The states are
Off The Station is disabled and not available for use.
On The Station is enabled and available for use.
Protocol The protocol state for the SDLC connection on this
State Station entity. The possible states are
Inactive This Station is not enabled. You must issue
an enable command before the SDLC entity can
activate the Station.
Normal The subentity can accept incoming connection
Disconnect requests or initiate outgoing connection
Mode requests.
Normal An SDLC logical link connection has been
Response established.
Mode
Pending This Station is enabled but other Peer Server
Active resources, must be active before the Station can
become active.
Pending You have issued a disable command for this
Inactive Station; no new sessions can use this Station.
The state will change to Inactive as soon as
all active sessions and non-SNA application
links on this Station have terminated.
5.6.3 – Characteristics
Address 2 characters Displays the address of the
hexadecimal secondary Station. The default is
40.
Group 2 characters Displays the group poll address for
Address hexadecimal Station. A value of 0 indicates the
Station is not in a group. The
default value is 0.
Transfer twa | tws Displays the link level transmit/-
Mode receive capability of the Station.
The default is twa. TWA is Two Way
Alternate; TWS is Two Way
Simultaneous.
Modulo normal | Displays whether the Station
extended supports normal response mode
(window size ranges from 1 to
7) or normal response mode
extended (window size ranges from 1
to 127). This attribute is ignored
for connections that perform XID3
negotiation. The default is normal.
Window Size (1-127) Displays the maximum number of
received I-frames that may be
outstanding before this station
requires an acknowledgment response.
This value allows for the detection
of erroneous sequence numbers in
received frames. The default is 7.
Send Frame (1-32764) Displays the maximum frame size
Size (excluding the header) this Station
can send. This value may be reduced
during pre-connection XID
negotiation or by the Station's
client. The default is 265.
Inactivity (0-7200) Displays the time (in seconds) to
Timer wait for a command before initiating
recovery action. This is used when
the Link is secondary. The default is
30.
Pass Limit (1-254) Displays the maximum number of
BLUs that can be sent to the second-
ary Station before starting data
transmission to the next Station in
the Link service order table. This is
used when the Link is Primary. The
default is 1.
Select (1-60000) Displays time (in milliseconds) to
Pause pause before sending a response with
the final bit set. This is used when
the LINK is secondary. The default
is 50.
Retry (0-255) Displays the time (in seconds) to
Sequence pause after completing a retry sequ-
Pause ence before beginning a new retry
sequence. This is used when the
Link is primary. The default is 0.
Not used at this time.
Retry (0-127) Displays the maximum number of
Sequence retry sequences allowed. This is used
Limit when the Link is primary. The
default is 0. Not used at this time.
Immediate no | yes Displays whether a Station
Poll subentity will be repolled when there
Retry is a reply time-out before proceeding
to next Station on the Link's service
order table. The default is no.
5.6.4 – Counters
Creation The time that the Station subentity was created.
Time
Connections The number of times a connection was established for
Established this Station.
Connections The number of times the SDLC connection was lost.
Lost
Connections The number of times an established connection was
Reset lost and subsequently re-established for this
Station by the snrm or snrme.
Polls The number of Information and Supervisory frames
sent by the primary or received by the secondary
station with the P-bit set.
Reply The number of times the local reply timer has
Timeouts expired after the transmission of a frame with
the P-bit set.
Secondary The number of times a primary station encountered a
Protocol protocol violation committed by an adjacent
Errors secondary station.
SNRM Frames The number of times a SNRM or SNRME frame was
sent by the primary or received by the secondary
station.
DISC Frames The number of times a DISC frame was sent by the
primary or received by the secondary station.
DM Frames The number of times a DM frame was sent by the
primary or received by the secondary station.
Octets Sent The total of the number of octets in I-frames and
UI-frames sent.
Octets The total of the number of octets in I-frames and
Received UI-frames received.
BLUs Sent The total of the number of I-frames and UI-frames
sent.
BLUs The total of the number of I-frames and UI-frames
Received received.
BLUs Resent The total of the number of I-frames and UI-frames
resent because of timeouts or rejects.
FRMR Frames The total number of FRMR-frames sent.
Sent
FRMR Frames The total number of FRMR-frames received.
Received
REJ Frames The number of SDLC REJ-frames sent.
Sent
REJ Frames The number of SDLC REJ-frames received.
Received
RNR Frames The number of times RNR-frames have been sent.
Sent
RNR Frames The number of times RNR-frames have been received.
Received
TEST Frames The total number of TEST-frames sent.
Sent
TEST Frames The total number of TEST-frames received.
Received
TESTs Received The total number of TEST-frames received with a
Invalid CRC bad CRC.
XID Frames The total number of XID frames sent.
Sent
XID Frames The total number of XID frames received.
Received
6 – Port Subentity
For each Enabled Station that establishes a connection, SDLC creates a Port entity.
6.1 – show
show sdlc port The show sdlc port command displays the attributes for the SDLC Port subentity. A Port subentity is created dynamically for each connection to a remote station. Each Port is created when a connection is established and deleted when the connection is terminated. Use the command show sdlc port * to display a listing of the existing Ports. Ex, ncl> show sdlc port 1 all counters
6.1.1 – Identifier
Name A unique value assigned to the Port by the SDLC
entity. The value is an unsigned integer.
6.1.2 – Status
UID Displays the entity's unique identifier, which
is generated when the Peer Server creates the entity.
Station Displays the name of the SDLC Link Station subentity
that the client specified in the connection request.
Client Displays the name of the client that connected to
this Port's Station.
Role Displays whether the station role is to be primary
or secondary when it becomes active.
Address Displays the address of the secondary station.
Transfer Displays the link-level transmit/receive capability
Mode for the connection, which is set to the transfer mode
characteristic of the SDLC Station. Might be altered
during XID negotiation.
Modulo Displays the Response Mode supported by the Station.
Normal Response Mode supports Send and Receive Window
Sizes of 1 to 7. Normal Response Mode Extended
supports Send and Receive Window Sizes of 1 to 127.
Send Window Displays the negotiated maximum number of transmitted
Size I-frames that may be outstanding before the adjacent
station requires an acknowledgment response. The
value is initialized as the SDLC Station window size
and might be reduced during preconnection XID
negotiation.
Receive Displays the negotiated maximum number
Window Size of received I-frames that may be outstanding
before this station requires an acknowledgment
response. The value is initialized as the SDLC
Station Window Size and might be reduced
during preconnection XID negotiation.
Send Frame Displays the negotiated maximum size of frames
Size (excluding header) sent by the connection. This
value is initialized as the SDLC receive frame
size. The value might be reduced during
preconnection XID negotiation.
Receive Displays the negotiated maximum size of frames
Frame Size (excluding header) received by the connection.
This value is initialized as the SDLC Station send
frame size. The value might be reduced during
preconnection XID negotiation.
6.1.3 – Counters
Creation Displays the time that the SDLC Port subentity
Time was created.
Polls Displays the number of frames sent by the primary or
received by the secondary with the P-bit set.
Octets Sent Displays the total number of octets sent in I-frames
and UI-frames.
Octets Displays the total number of octets received
Received in I-frames and UI-frames.
BLUs Sent Displays the total number of I-frames and
UI-frames sent.
BLUs Displays the total number of I-frames and UI-frames
Received received.
BLUs Resent Displays the total number of I-frames and UI-frames
retransmitted due to timeouts or rejects.