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This guide will help you check for common problems that cause the log ” -non-loopback- is deprecated as it picks an arbitrary interface. specify explicit scope(s); interface(s); address(es); or hostname(s) instead ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: network.
Log Context
Log “_non_loopback_ is deprecated as it picks an arbitrary interface. specify explicit scope(s); interface(s); address(es); or hostname(s) instead” classname is NetworkService.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
return NetworkUtils.getFirstNonLoopbackAddresses();
case "non_loopback:ipv4":
logger.warn("_non_loopback_ is deprecated as it picks an arbitrary interface. specify explicit scope(s); interface(s); address(es); or hostname(s) instead");
return NetworkUtils.filterIPV4(NetworkUtils.getFirstNonLoopbackAddresses());
case "non_loopback:ipv6":
logger.warn("_non_loopback_ is deprecated as it picks an arbitrary interface. specify explicit scope(s); interface(s); address(es); or hostname(s) instead");
return NetworkUtils.filterIPV6(NetworkUtils.getFirstNonLoopbackAddresses());
default:
/* an interface specification */
if (host.endsWith(":ipv4")) {
host = host.substring(0; host.length() - 5);
