Table 5: Mtu Configuration Example Values; Figure 4: Mtu Configuration Example - Alcatel-Lucent 7210 SAS E OS Configuration Manual

Modifying MTU Defaults
MTU parameters can be modified on the port level.
•
The default MTU values should be modified to ensure that packets are not dropped due to frame
size limitations.
Configuration Example
In order for the maximum length service frame to successfully travel from a local ingress SAP to a
remote egress SAP, the MTU values configured on the port on which the local ingress SAP is
provisioned and the port on which egress SAP is provisioned must be coordinated to accept the
maximum frame size the service can forward. For example, the targeted MTU values to configure
for an Epipe service (ALA-A and ALA-B) are displayed in
Since ALA-A uses Dot1q encapsulation, the port 1/1/1 MTU must be set to 1518 to be able to
accept a 1514-byte service frame
port's MTU must be set to at least 1518 as well. Finally, the MTU of ALA-B's SAP (access port
1/1/2) must be at least 1514, as it uses null encapsulation.

Table 5: MTU Configuration Example Values

Port (slot/MDA/port)
Mode type
MTU
7210 SAS E Interface Configuration Guide
The port-level MTU parameters configure the maximum payload MTU size for an
Ethernet port that is part of a multilink bundle or LAG.
ALA-A
SAP
SAP
1/1/24
1/1/1
encap
encap:
:100.*
:100

Figure 4: MTU Configuration Example

Access (SAP)
1/1/1
access (dot1q)
1518
ALA-B
SAP
SAP
1/1/18
1/1/1
encap
encap:
:100.*
:null
(seeTable 5 for MTU default values). Each of the access uplink
ALA-A
Access
Uplink (SAP)
1/1/24
access-uplink
(QinQ)
1518
Interface Configuration
Figure 4.
OSSG012-7210E
ALA-B
Access Access (SAP)
Uplink (SAP)
1/1/18 1/1/2
access-uplink access (null)
(QinQ)
1518 1514
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