Alexey Serbin has uploaded this change for review. ( http://gerrit.cloudera.org:8080/15274
Change subject: [clock] relax version constraint for NTP response ...................................................................... [clock] relax version constraint for NTP response As it turned out, there are NTP servers in the wild that respond back with version 4 even if they support version 3 and the client sent version 3 in its request packet. In this particular case, it was the dedicated server in one of r5ad.xlarge EC2 instances provisioned in EC2 us-west-2 (interestingly enough, the dedicated NTP servers of other EC2 t2.large instances in my test cluster behaved as expected). The observed behavior of the dedicated NTP server at the mentioned r5ad.xlarge instance appears to contradict the information presented in RFC 5905 (appendix A.5.3. fast_xmit()) and RFC 4330 (Secion 5. SNTP Client Operations), but it is what it is. Because the former strict constraint in the built-in NTP client, it was not able to work with such NTP servers. This patch relaxes the requirement for expected NTP versions sent in a server's response. For details, see the corresponding comment in builtin_ntp.cc. As for testing and verification, I ran the updated code and verified that the built-in NTP client is now able to work with the NTP server mentioned above, tracking true time as expected. As a side note, I also explored options to implement a test scenario using MiniChronyd, but I found no way to configure chronyd to behave in a non-conforming manner described above. Change-Id: I1df3549616bbced696380458978c33264ed636c9 --- M src/kudu/clock/builtin_ntp.cc 1 file changed, 17 insertions(+), 2 deletions(-) git pull ssh://gerrit.cloudera.org:29418/kudu refs/changes/74/15274/1 -- To view, visit http://gerrit.cloudera.org:8080/15274 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: kudu Gerrit-Branch: master Gerrit-MessageType: newchange Gerrit-Change-Id: I1df3549616bbced696380458978c33264ed636c9 Gerrit-Change-Number: 15274 Gerrit-PatchSet: 1 Gerrit-Owner: Alexey Serbin <[email protected]>
