DNSTracer

A tool to automate troubleshooting DNS issues for delegated zones

Usage

Head to the Releases Page and download the release for either Darwin(Mac) or Linux Be sure to change the permissions so that the binary is executable

chmod +x dnstracer

Get Help

$ ./dnstracer  -h
Usage: dnstracer [-dhis] [-e value] [parameters ...]
 -d, --debug     Enable debug output
 -e, --endpoint=value
                 The name of the redis endpoint eg:
                 redis-10000.foo.example.com
 -h, --help      display help
 -i, --internal  Use only internal resolvers (only on Linux)
 -s, --suggest   Suggest possible fixes

Resolution Settings

If not set to use internal resolvers, dnstracer will attempt to use Google and Cloudflare's publicly available DNS servers to troubleshoot. When the Redis Enterprise servers are not publicly available use the internal option

Check a cluster we know is broken

$ ./dnstracer  -d redis-10002.azure1.mague.com
Error - run with --debug for more information or run with --suggest for hints on how to fix

Check a cluster and provide some possible suggestions for fixes

$ ./dnstracer  -e redis-10002.azure1.mague.com --suggest
--------------------------------
          NS Record Test: OK
        Glue Record Test: OK
          NS Access Test: ERROR
          SOA Match Test: OK
           A Record Test: OK
--------------------------------
Suggestions for redis-10002.azure1.mague.com
--------------------------------
NS Access Suggestions
--------------------------------
Unable to query one or more of the delegated nameservers

Please make sure the DNS server is running with the command
    supervisorctl status  pdns_server

Please make sure the DNS port is not firewalled to external sources

Please use the following commands to troubleshoot:
    dig +noall +answer NS azure1.mague.com @20.36.28.197
    dig +noall +answer NS azure1.mague.com @40.65.114.126
    dig +noall +answer NS azure1.mague.com @52.250.9.35

If all else fails and you've found a new failure scenario I may have missed : run with debug and submit an issue

$ ./dnstracer  -e redis-10002.azure1.mague.com --debug
--------------------------------
          NS Record Test: OK
        Glue Record Test: OK
          NS Access Test: ERROR
          SOA Match Test: OK
           A Record Test: OK
--------------------------------
Results Debug:
{ResultA:true ResultNS:true ResultGlue:true ResultAccess:true ResultSOAMatch:true}
--------------------------------
&{LocalA:[20.36.28.197] DNS2A:[20.36.28.197] DNS1A:[20.36.28.197] LocalNS:[ns1.azure1.mague.com. ns2.azure1.mague.com. ns3.azure1.mague.com.] DNS2NS:[ns1.azure1.mague.com. ns2.azure1.mague.com. ns3.azure1.mague.com.] DNS1NS:[ns1.azure1.mague.com. ns2.azure1.mague.com. ns3.azure1.mague.com.] LocalGlue:[20.36.28.197 40.65.114.126 52.250.9.35] DNS2Glue:[20.36.28.197 40.65.114.126 52.250.9.35] DNS1Glue:[20.36.28.197 40.65.114.126 52.250.9.35] PublicMatchA:true LocalMatchA:true PublicMatchNS:true LocalMatchNS:true PublicMatchGlue:true LocalMatchGlue:true EndpointStatus:[true false true]}
{ResultA:true ResultNS:true ResultGlue:true ResultAccess:true ResultSOAMatch:true}

Error - run with --debug for more information or run with --suggest for hints on how to fix

Redislabs-Solution-Architects / dnstracer