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https://issues.apache.org/jira/browse/HDFS-13082?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17154055#comment-17154055
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Daniel Howard commented on HDFS-13082:
--------------------------------------

I found a comment that implies that Linux doesn't handle cookie verification:[1]
bq. This discussion comes up pretty much every time someone writes a new NFS 
server and/or filesystem. The thing that neither RFC1813, RFC3530, or RFC5661 
have done is come up with sane semantics for how a NFS client is supposed to 
recover from the above scenario. What do I do with things like 
telldir()/seekdir() cookies? How do I recover my 'current position' in the 
readdir() stream?
bq. IOW: how do I fake up POSIX semantics to the applications?
bq. 
bq. Until the recovery question is answered, the Linux client will continue to 
ignore the whole "cookie verifier" junk...

[1]: 
https://linuxlists.cc/l/17/linux-nfs/t/2933109/readdir_from_linux_nfs4_client_when_cookieverf_is_no_longer_valid

Here is a reference to cookieverf being removed from an Android kernel:
https://gitlab.incom.co/CM-Shield/android_kernel_nvidia_shieldtablet/commit/c3f52af3e03013db5237e339c817beaae5ec9e3a

> cookieverf mismatch error over NFS gateway on Linux
> ---------------------------------------------------
>
>                 Key: HDFS-13082
>                 URL: https://issues.apache.org/jira/browse/HDFS-13082
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: hdfs
>    Affects Versions: 2.7.3
>            Reporter: Dan Moraru
>            Priority: Minor
>
> Running 'ls' on some directories over an HDFS-NFS gateway sometimes fails to 
> list the contents of those directories.  Running 'ls' on those same 
> directories mounted via FUSE works.  The NFS gateway logs errors like the 
> following:
> 2018-01-29 11:53:01,130 ERROR org.apache.hadoop.hdfs.nfs.nfs3.RpcProgramNfs3: 
> cookieverf mismatch. request cookieverf: 1513390944415 dir cookieverf: 
> 1516920857335
> Reviewing 
> hadoop-hdfs-project/hadoop-hdfs-nfs/src/main/java/org/apache/hadoop/hdfs/nfs/nfs3/RpcProgramNfs3.java
>  suggested that  these errors can be avoided by setting 
> nfs.aix.compatibility.mode.enabled=true, and that is indeed the case.  The 
> documentation lists https://issues.apache.org/jira/browse/HDFS-6549 as a 
> known issue, but also goes on to say that "regular, non-AIX clients should 
> NOT enable AIX compatibility mode. The work-arounds implemented by AIX 
> compatibility mode effectively disable safeguards to ensure that listing of 
> directory contents via NFS returns consistent results, and that all data sent 
> to the NFS server can be assured to have been committed."   Server and client 
> is this case are one and the same, running Scientific Linux 7.4.
>  



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