The github.com/beevik/ntp package was recently updated with some
API changes that broke node_exporter. This commit fetches the
latest version of the ntp package and brings node_exporter in
line with the latest API.
* Add metrics from SNTPv4 packet to ntp collector & add ntpd sanity check
1. Checking local clock against remote NTP daemon is bad idea, local
ntpd acting as a client should do it better and avoid excessive load on
remote NTP server so the collector is refactored to query local NTP
server.
2. Checking local clock against remote one does not check local ntpd
itself. Local ntpd may be down or out of sync due to network issues, but
clock will be OK.
3. Checking NTP server using sanity of it's response is tricky and
depends on ntpd implementation, that's why common `node_ntp_sanity`
variable is exported.
* `govendor add golang.org/x/net/ipv4`, it is dependency of github.com/beevik/ntp
* Update github.com/beevik/ntp to include boring SNTP fix
* Use variable name from RFC5905
* ntp: move code to make export of raw metrics more explicit
* Move NTP math to `github.com/beevik/ntp`
* Make `golint` happy
* Add some brief docs explaining `ntp` #655 and `timex` #664 modules
* ntp: drop XXX comment that got its decision
* ntp: add `_seconds` suffix to relevant metrics
* Better `node_ntp_leap` comment
* s/node_ntp_reftime/node_ntp_reference_timestamp_seconds/ as requested by @discordianfish
* Extract subsystem name to const as suggested by @SuperQ
* Add diskstats collector for Darwin
* Update year in the header
* Update README.md
* Add github.com/lufia/iostat to vendored packages
* Change stats to follow naming guidelines
* Add a entry of github.com/lufia/iostat into vendor.json
* Remove /proc/diskstats from description
* Add qdisc collector for Linux
This collector gathers basic queueing discipline metrics via netlink,
similarly to what `tc -s qdisc show` does.
* qdisc collector: nl-specific code moved, names fixed
- netlink-specific parts moved to github.com/ema/qdisc
- avoid using shortened names
- counters renamed into XXX_total
* Get rid of parseMessage error checking leftover
* Add github.com/ema/qdisc to vendored packages
* Update help texts and comments
* Add qdisc collector to README file
* qdisc collector end-to-end testing
* Update qdisc dependency to latest version
Update github.com/ema/qdisc dependency to revision 2c7e72d, which
includes unit testing.
* qdisc collector: rename "iface" label into "device"
Previously the raw time difference was used which includes the network trip time
between the node and the ntp server. This makes setting alerts off the value
troublesome as it depends on the latency as well as the clock offset.
