Configuring Aggregated SONET/SDH Interfaces
The JUNOS software enables link aggregation of SONET/SDH interfaces; this is similar to Ethernet link aggregation, but is not defined in a public standard. The JUNOS software balances traffic across the member links within an aggregated SONET/SDH bundle based on the Layer 3 information carried in the packet. This implementation uses the same load balancing algorithm used for per-packet load balancing. For information about per-packet load balancing, see the JUNOS Routing Protocols Configuration Guide.
You configure an aggregated SONET/SDH virtual link by specifying the link number as a physical device and then associating a set of physical interfaces that have the same speed. Channelized OC IQ and IQE PICs do not support SONET aggregation.
By default, no aggregated SONET/SDH interfaces are created. You must define the number of aggregated SONET/SDH interfaces by including the device-count statement at the [edit chassis aggregated-devices sonet] hierarchy level:
The maximum number of aggregated interfaces is 16. The aggregated SONET/SDH interfaces are numbered from as0 through as15. For more information, see the JUNOS Services Interfaces Configuration Guide.
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Note: SONET/SDH aggregation is proprietary to the JUNOS software and might not work with other software. |
To configure aggregated SONET/SDH interfaces, assign a number for the aggregated SONET/SDH interface asx at the [edit interfaces] hierarchy level:
The following example shows an aggregated SONET/SDH configuration:
- [edit interfaces]
- as0 {
-
- aggregated-sonet-options {
- minimum-links 1;
- oc3;
- }
-
- unit 0 {
-
- family inet {
-
- address 10.2.11.1/32 {
- destination 10.2.11.3;
- }
- }
- }
- }
You also need to specify the constituent physical interfaces by including the aggregate statement at the [edit interfaces interface-name sonet-options] hierarchy level; for more information, see Configuring SONET/SDH Link Aggregation. You can optionally specify other physical properties that apply specifically to the aggregated SONET/SDH interfaces; for details, see Configuring SONET/SDH Physical Interface Properties. For a sample configuration, see Example: Configuring Aggregated SONET/SDH Interfaces.
To remove the configuration statements related to asx and set the aggregated SONET/SDH interface to down state, delete the interface from the configuration:
However, the aggregated SONET/SDH interface is not deleted until you delete the chassis aggregated-devices sonet device-count configuration statement.
You can configure the following aggregated SONET/SDH properties:
Configuring SONET/SDH Link Aggregation
On SONET/SDH interfaces, you can associate a physical interface with an aggregated SONET/SDH interface. To associate the interface with an aggregated SONET/SDH link, include the aggregate statement at the [edit interfaces interface-name sonet-options] hierarchy level:
x is the interface instance number and can be from 0 through 15, for a total of 16 aggregated interfaces. You should not mix SONET and SDH mode on the same aggregated interface. You must also include a statement configuring asx at the [edit interfaces] hierarchy level. For a sample configuration, see Example: Configuring Aggregated SONET/SDH Interfaces.
Configuring Aggregated SONET/SDH Link Speed
On aggregated SONET/SDH interfaces, you can set the required link speed for all interfaces included in the bundle, or specify that the bundle contains interfaces with mixed interface speeds.
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Note: For nonconcatenated interfaces on aggregated SONET/SDH interfaces, you can configure the link speed of the aggregate to match the speed of the nonconcatenated interface. For example, an OC12 PIC can have nonconcatenated interfaces with a link speed of OC3. |
To set the required link speed or specify mixed interface speeds, include the link-speed statement at the [edit interfaces interface-name aggregated-sonet-options] hierarchy level:
The link speed can be one of the following values:
- oc3—Links are OC3c or STM1c.
- oc12—Links are OC12c or STM4c.
- oc48—Links are OC48c or STM16c.
- oc192—Links are OC192c or STM64c.
- oc768—Links are OC768c or STM256c.
Configuring Aggregated SONET/SDH Minimum Links
On aggregated SONET/SDH interfaces, you can configure the minimum number of links that must be up for the bundle as a whole to be labeled up. By default, only one link must be up for the bundle to be labeled up.
To configure the minimum number of links, include the minimum-links statement at the [edit interfaces interface-name aggregated-sonet-options] hierarchy level:
- [edit interfaces interface-name aggregated-sonet-options]
- minimum-links number;
On a T-series, TX matrix routing platform with SONET interfaces, the valid range for minimum-links number is from 1 through 16. When the maximum value (16) is specified, all configured links of a bundle must be up for the bundle to be labeled up.
On all other router platforms, the range of valid values for minimum-links number is 1 through 8 and the maximum number of links supported in an aggregate is eight. When the maximum value (8) is specified, all configured links of a bundle must be up for the bundle to be labeled up.
Configuring Filters or Sampling on Aggregated SONET/SDH Links
To set up firewall filters or sampling on aggregated SONET/SDH interfaces, you must configure the asx interface with these properties. The filters function in the same manner as on other interfaces.
To configure a filter, include the filter statement:
- filter {
- input input-filter-name;
- output output-filter-name;
- }
You can include this statement at the following hierarchy levels:
- [edit interfaces as x unit logical-unit-number]
- [edit logical-systems logical-system-name interfaces asx unit logical-unit-number]
You must also configure separate statements that define the properties of the filter. For more information, see the JUNOS Policy Framework Configuration Guide and Examples: Configuring Filters or Sampling on Aggregated SONET/SDH Links.
Examples: Configuring Filters or Sampling on Aggregated SONET/SDH Links
Configure filtering on aggregated SONET/SDH interfaces:
- [edit interfaces]
- asx {
-
- unit 0 {
-
- family inet {
-
- address 10.2.11.1/32 {
- destination 10.2.11.3;
- }
-
- filter {
- input input-filter-name;
- output output-filter-name;
- }
- }
- }
- }
Defining the Filter
- [edit firewall]
- filter input-filter-name {
-
- term match-any-input {
-
- then {
- accept;
- }
- }
- }
- filter output-filter-name {
-
- term match-any-output {
-
- then {
- accept;
- }
- }
- }
Configuring Sampling on an Aggregated SONET/SDH Interface
- [edit interfaces]
- asx {
-
- unit 0 {
-
- family inet {
-
- address 10.2.11.1/32 {
- destination 10.2.11.3;
- }
-
- filter {
- input input-sampler-name;
- }
- }
- }
- }
Defining the Sampling Filter and the Forwarding Action
- [edit firewall]
- filter input-sampler-name {
-
- term match-any-input {
-
- then {
- sample;
- accept;
- }
- }
- }
- [edit forwarding-options]
- sampling {
-
- input {
-
- family inet {
- rate 10000;
- run-length 1;
- }
- }
- }
Example: Configuring Aggregated SONET/SDH Interfaces
The following configuration is sufficient to get an aggregated SONET/SDH interface up and running:
- [edit interfaces]
- as0 {
-
- aggregated-sonet-options {
- minimum-links 1;
- link-speed oc3;
- }
-
- unit 0 {
-
- family inet {
-
- address 10.2.11.1/32 {
- destination 10.2.11.3;
- }
- }
- }
- }
- [edit chassis]
- aggregated-devices {
-
- sonet {
- device-count 15;
- }
- }
- [edit interfaces]
- so-1/3/0 {
-
- sonet-options {
- aggregate as0;
- }
- }

