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RBridges: Operations, Administration, and Maintenance (OAM) Support. David Bond, Vishwas Manral UNH-IOL, IP Infusion draft-bond-trill-rbridge- oam -00. Outline. OAM Tools Route Respond Traceroute Hop Count Traceroute RBridge Ping Error Reporting OAM Option vs. OAM Frame PDU Formats
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RBridges: Operations, Administration, and Maintenance (OAM) Support David Bond, Vishwas Manral UNH-IOL, IP Infusion draft-bond-trill-rbridge-oam-00
Outline • OAM Tools • Route Respond Traceroute • Hop Count Traceroute • RBridge Ping • Error Reporting • OAM Option vs. OAM Frame • PDU Formats • Security
Route Respond Traceroute • RBridge originating the traceroute sends Route Respond Message • Each transit RBridge and the egress RBridge send an Echo Reply Message • Similar to the IP Option traceroute in RFC 1393
Route Respond Traceroute • Multi-destination traceroute's allowed • Tree discovered • Normally end stations not involved • Possible to “tag” real traffic with traceroute +-----+ +-------+ +-------+ +-------+ +-----+ | ESa +--+ RB0 +---+ RB1 +---+ RB2 +--+ ESb | +-----+ |ingress| |transit| |egress | +-----+ +-------+ +-------+ +-------+ Time RB0 RB1 RB2 . (1)-------> (1) -------> | . | <------- (2) | . | <------- (3) <-------(3)
Hop Count Traceroute • RBridge originating the traceroute sends Echo Request Message with hop count of 0 • Each transit RBridge and the egress RBridge send a Hop Count Error Message • Based on traditional IP traceroute
Hop Count Traceroute • Con: more OAM traffic • Pro: no special processing needed on transit until hop count error occurs. +-----+ +-------+ +-------+ +-------+ +-----+ | ESa +--+ RB0 +---+ RB1 +---+ RB2 +--+ ESb | +-----+ |ingress| |transit| |egress | +-----+ +-------+ +-------+ +-------+ Time RB0 RB1 RB2 . (1)-------> | | . | <------- (2) | . (3)-------> (3) -------> | . | <------- (4) <-------(4)
RBridge Ping • RBridge originating the ping sends Echo Request Message • Egress RBridge sends an Echo Reply Message • Similar to ICMP Ping
Error Reporting • Error Message sent to ingress RBridge when error seen in a TRILL frame • A frame format for reporting errors • MTU Error • Hop Count Error • Generic Error • Type sub-code
OAM Option vs. OAM Frame • Draft presents OAM Option • Problem: some data paths may slow path option tagged frames • CItE option allows ASIC to not do this, but not all RBridges may be implement in this way • Limits size of message • We could also use an encapsulated TRILL OAM frame • The inner ethernet header ethertype could be TRILL or a TRILL OAM Ethertype • This does not allow tagging of real traffic • Later drafts will specify both an OAM Option and an OAM Frame
OAM Option vs. OAM Frame +--------------------------------+ | Outer Ethernet Header | +--------------------------------+ | TRILL Header | +--------------------------------+ | TRILL OAM Option | +--------------------------------+ | Dummy Inner Ethernet Header | +--------------------------------+ | Dummy Ethernet Payload | +--------------------------------+ +--------------------------------+ | Outer Ethernet Header | +--------------------------------+ | TRILL Header | +--------------------------------+ | Inner Ethernet Header | +--------------------------------+ | TRILL or TRILL OAM Ethertype | +--------------------------------+ | TRILL OAM Data | +--------------------------------+
PDU Formats • TRILL OAM Option Common Initial Part • These messages do not add to the base option: • Echo Request Message • Route Respond Request Message • Generic Error
PDU Formats • Echo Reply Message
PDU Formats • Hop Count Zero Error Message • MTU Error Message
PDU Formats • Type, Length, Value (TLV) Encodings • Padding • Next Hop Nickname • Incoming Port ID • Outgoing Port ID • Outgoing Port MTU
Security • Future OAM security option will secure frames • Rate limiting important • Configuration of transmission of OAM messages on per RBridge/port basis