Fix DNS resolution failure on Linux when host is an IP address (#50)#51
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CritasWang wants to merge 1 commit intoapache:mainfrom
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Fix DNS resolution failure on Linux when host is an IP address (#50)#51CritasWang wants to merge 1 commit intoapache:mainfrom
CritasWang wants to merge 1 commit intoapache:mainfrom
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…e#50) TSocketTransport(string host, ...) unconditionally calls Dns.GetHostEntry, which on Linux performs reverse-then-forward lookup even for literal IPs, causing 'Name or service not known' SocketException. Pre-parse host with IPAddress.TryParse and use the IPAddress overloads of TSocketTransport / TTlsSocketTransport so IP literals bypass DNS entirely. Hostnames still go through the existing string-based path.
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Summary
Fixes #50.
On Linux,
SessionPool.CreateAndOpenfails withThrift.Transport.TTransportException: Name or service not knowneven when a valid IP literal is supplied. Root cause: the 4-argTSocketTransport(string host, int port, TConfiguration, int timeout)constructor unconditionally callsDns.GetHostEntry(host). On Linux,GetHostEntrywith an IP string performs reverse lookup first, then re-resolves the returned hostname forward — if either step fails, aSocketExceptionis thrown. Windows is more permissive and hides the bug.Fix
Pre-parse the host with
IPAddress.TryParse:TSocketTransport(IPAddress, …)/TTlsSocketTransport(IPAddress, …, cert)overload, which skips DNS entirely.File changed:
src/Apache.IoTDB/SessionPool.cs(+14 / -3).Test plan
dotnet build -c Releasepasses on all target frameworks (net5.0,net6.0,netstandard2.1,netstandard2.0,net461) — 0 errors.SessionPool(host="<IPv4>", port=6667, …)on a Linux host whose/etc/hostsdoes not map the IP; expect successful connection.localhost) — expect unchanged behavior.