Trace the SCION route to a remote SCION AS using SCMP traceroute packets
‘traceroute’ traces the SCION path to a remote AS using SCMP traceroute packets.
If any packet is dropped, traceroute will exit with code 1. On other errors, traceroute will exit with code 2. The paths can be filtered according to a sequence. A sequence is a string of space separated HopPredicates. A Hop Predicate (HP) is of the form ‘ISD-AS#IF,IF’. The first IF means the inbound interface (the interface where packet enters the AS) and the second IF means the outbound interface (the interface where packet leaves the AS). 0 can be used as a wildcard for ISD, AS and both IF elements independently.
|Match ISD 1:||1|
|Match AS 1-ff00:0:133:||1-ff00:0:133|
|Match IF 2 of AS 1-ff00:0:133:||1-ff00:0:133#2|
|Match inbound IF 2 of AS 1-ff00:0:133:||1-ff00:0:133#2,0|
|Match outbound IF 2 of AS 1-ff00:0:133:||1-ff00:0:133#0,2|
|sequence:||“1-ff00:0:133#0 1-ff00:0:120#2,1 0 0 1-ff00:0:110#0”|
The above example specifies a path from any interface in AS 1-ff00:0:133 to two subsequent interfaces in AS 1-ff00:0:120 (entering on interface 2 and exiting on interface 1), then there are two wildcards that each match any AS. The path must end with any interface in AS 1-ff00:0:110.
|sequence:||“1-ff00:0:133#1 1+ 2-ff00:0:1? 2-ff00:0:233#1”|
The above example includes operators and specifies a path from interface 1-ff00:0:133#1 through multiple ASes in ISD 1, that may (but does not need to) traverse AS 2-ff00:0:1 and then reaches its destination on 2-ff00:0:233#1.
|?||(the preceding HopPredicate may appear at most once)|
|+||(the preceding ISD-level HopPredicate must appear at least once)|
|*||(the preceding ISD-level HopPredicate may appear zero or more times)|
scion traceroute [flags] <remote>
scion traceroute 1-ff00:0:110,10.0.0.1
--dispatcher string Path to the dispatcher socket (default "/run/shm/dispatcher/default.sock") --epic Enable EPIC. -h, --help help for traceroute -i, --interactive interactive mode --isd-as isd-as The local ISD-AS to use. (default 0-0) -l, --local ip Local IP address to listen on. (default zero IP) --log.level string Console logging level verbosity (debug|info|error) --no-color disable colored output --refresh set refresh flag for path request --sciond string SCION Deamon address. (default "127.0.0.1:30255") --sequence string Space separated list of hop predicates --timeout duration timeout per packet (default 1s) --tracing.agent string Tracing agent address