Consider using script us5.py which sets the subscriber ID (sub_ident) based on the circuit-id in the DHCP message.
Configure the URL to this script in a sub-ident-policy as follows:
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sub-ident-policy "DSLAM" create
description "Parse circuit IDs from different DSLAMs"
primary
script-url "ftp://198.51.100.0/py/us5.py"
no shutdown
exit
exit
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And attach this sub-ident-policy to the sub-sla-mgmt from a SAP:
A:dut-A>config>service>vpls>sap# info
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dhcp
description "client side
lease-populate 50
no shutdown
exit
anti-spoof ip-mac
sub-sla-mgmt
sub-ident-policy "DSLAM"
no shutdown
exit
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