Support Redis dns discovery #4590
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pkg/chunk/cache/redis_client.go
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| if err != nil { | ||
| return nil, err | ||
| } | ||
| addrs, err := net.LookupHost(host) |
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This looks to me like a straightforward DNS lookup - why do you call it "Cluster configuration" ?
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This is a term that AWS uses (only?), the cluster configuration is an A record which resolves all node addresses in a cluster, I used cluster configuration to hint that it could be single DNS record pointing to a cluster and reuse the AWS term.
But let me know if you have a suggestion for naming a more generic DNS record pointing to a redis cluster nodes.
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Hi siavashs, first of all, thank you for the contribution!
There is actually a service discover through DNS mechanism for memcached called; here is the doc. For Redis I think we should be consistent and use similar way to configure DNS look up.
Hi @alvinlin123 Thanks for pointing that out. Yes, I think that's a better solution. |
siavashs
changed the title
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I've updated the PR to add support for dns discovery as suggested. |
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@siavashs Sorry for the delay, but I just remembered this pending PR. Would you kindly fix the lint error? Else the change looks good to me |
| } | ||
| resolved, err := resolver.Resolve(ctx, name, dns.QType(qtype)) | ||
| if err != nil { | ||
| level.Error(logger).Log("msg", "failed to resolve redis address", "addr", addr, "err", err) |
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Stylistically, is it better to log here rather than returning the error?
What happens if all the addresses result in error?
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Good point, is it better to return an error on first address resolve failure or return only if all addresses fail to resolve?
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I went with the second option to return an error if no addresses are resolved.
The go-redis options requires multiple redis addresses for a cluster. In some scenarios like AWS ElastiCache, a single configuration endpoint is used to resolve all cluster nodes. This change adds experimental support for redis dns discovery. This is a similar implementation to memcached ds but with just a resolver. Signed-off-by: Siavash Safi <siavash.safi@gmail.com>
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The CI tests have failed because of a timeout but I can't rerun them. |
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This issue has been automatically marked as stale because it has not had any activity in the past 60 days. It will be closed in 15 days if no further activity occurs. Thank you for your contributions. |
What this PR does:
The go-redis options requires multiple redis addresses for a cluster.
In some scenarios like AWS ElastiCache, a single configuration endpoint is used to resolve all cluster nodes.
This change adds experimental support for redis dns discovery.
This is a similar implementation to memcached ds but with just a resolver.
Signed-off-by: Siavash Safi siavash.safi@gmail.com
Which issue(s) this PR fixes:
Checklist
CHANGELOG.mdupdated - the order of entries should be[CHANGE],[FEATURE],[ENHANCEMENT],[BUGFIX]