PPPOE subscribers unable to login due to entry already exists in the ifl map. This issue will happen once the maximum limit reached.
On Junos platforms with Advanced Forwarding Toolkit (AFT) line cards, premature release of the Variable Based Forwarding index before proper cleanup from the interface map caused lookup failures for new logical interfaces (IFLs), resulting in flow creation errors.
This issue occurs in a Broadband Edge (BBE) setup with dynamic subscribes, If the subscriber logs out and the index is freed too early, new subscribers may fail to create flows due to missing IFL mappings. To track this issue, use the command line 'show log messages'. The below logs noticed during the issue:
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:HANDLE-IFL: Entry already exists in the ifl map. iflIndex:1 iflType:vlan-demux iflTemplate:true iflExternal:false iflPseudoIflIndex:417 iflBindPointType:ifl iflVarCount:0 iflMapSize:49
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:HANDLE-IFL: Failed to add entry into ifl map. iflIndex:1 iflType:vlan-demux iflTemplate:true
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:HANDLE_IFL_TRIO: Ifl initialization failed. iflIndex:1 iflType:vlan-demux iflTemplate:true error:File exists
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:: Failed to setup the ifl:1
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:PLATFORM-TRIO: Failed to create ifl. iflIndex:1 iflType:vlan-demux iflFlags: template,
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:FLOW-PROCESSOR: Failed to create ifl. iflIndex:1 iflType:vlan-demux iflFlags: template,
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:FLOW-PROCESSOR: Failed to create flow ifl. iflIndex:1 iflType:vlan-demux iflFlags: template,
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:FLOW-PROCESSOR: Template value inline flow add failed to create flow ifl. msgType:flow id:74453 genNum:74319 flowType:vlan-demux
aftd-trio[18180]: %PFE-3: [t:18323] [Error] VBFMAN:FLOW-PROCESSOR: Flow Processing failed. msgType:flow id:74453 genNum:74319 flowType:vlan-demux
Issue fixed in junos:22.4R3-S2 junos:23.2R2-J8 junos:23.2R2-S1 junos:23.4R2 junos:24.2R1 junos:24.2R2 junos:24.3R1.