Repo1.maven.org: Temporary failure in name resolution

I’m having trouble with consistent DNS resolution/download errors on my builds:

Example 1

Log:
Error |
396Resolve error obtaining dependencies: Could not transfer artifact org.grails.plugins:tomcat:zip:8.0.50 from/to repo1_maven_org_maven2_ (Central Repository:): repo1.maven.org: Temporary failure in name resolution (Use --stacktrace to see the full trace)

Example 2

Log:
fetch …dl-cdn.alpinelinux.org/alpine/v3.9/main/x86_64/APKINDEX.tar.gz
1158ERROR: …dl-cdn.alpinelinux.org/alpine/v3.9/main: temporary error (try again later)
1159fetch …dl-cdn.alpinelinux.org/alpine/v3.9/community/x86_64/APKINDEX.tar.gz
1160ERROR: …/dl-cdn.alpinelinux.org/alpine/v3.9/community: temporary error (try again later)
1161v3.9.3-99-g09a6d0afd5 […dl-cdn.alpinelinux.org/alpine/v3.9/main]
1162v3.9.3-94-g8dce0df69b [http://dl-cdn.alpinelinux.org/alpine/v3.9/community]
11632 errors; 9767 distinct packages available

Locally I’m able to resolve repo1.maven.org and download Apline Linux packages that Travis fails to download. This looks like a Travis error.

Any idea how to fix this?

Thanks,
Kare