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Dear all,

We are running Xrootd 5.4.2-3 in an redirector (xrootd.phy.bris.ac.uk:1094) → gateway (io-37-02.acrc.bris.ac.uk:1194) setup on CentOS 7 and connect storage via xrootd-hdfs (async disabled).
We offer xrootd and https-over-xrootd, our issue is mostly for the latter.

The issue we are experiencing can be summarized in the mermaid graph:

sequenceDiagram
    participant Client
    participant XrootD Redirector
    participant XrootD Gateway
    participant HDFS

    Client ->> XrootD Redirector: rename /path/to/file /path/to/file.new
    XrootD Redirector ->> XrootD Gateway: rename /path/to/file /path/to/file.new
    XrootD Gateway ->> HDFS: rename /path/to/file /path/to/file.new
    HDFS -->> XrootD Gateway: rename done
    Note left of Client: Waits 5 seconds
    Client ->> XrootD Redirector: stat /path/to/file.new
    XrootD Redirector ->> Client: /path/to/file.new does not exist

and is explained in more detail in #235 (comment).
In short: file is renamed on disk, but redirector thinks it is not there.

This is not an issue for most VOs, but operational tests (OPS VO) are failing - very bad.
Since this is unlikely to be solved internally in xrootd (based on the comment in issue 235), I was wondering if it would be possible to solve it at config level.

Can we change stat/propfind requests to

always query the gateway and file system:

sequenceDiagram
    participant Client
    participant XrootD Redirector
    participant XrootD Gateway
    participant HDFS

    Client ->> XrootD Redirector: stat /path/to/file.new
    XrootD Redirector ->> XrootD Gateway: stat /path/to/file.new
    XrootD Gateway ->> HDFS: stat /path/to/file.new
    HDFS -->> XrootD Gateway: stat results
    XrootD Gateway -->> Client: stat results

or can we change the redirector to directly query the file system (read-only):

sequenceDiagram
    participant Client
    participant XrootD Redirector
    participant HDFS

    Client ->> XrootD Redirector: stat /path/to/file.new
    XrootD Redirector ->> HDFS: stat /path/to/file.new
    HDFS -->> XrootD Redirector: stat results
    XrootD Redirector -->> Client: stat results

The particular test we are failing: argo-mon - not sure if this is available to everyone.

Apparently, more info on that test is on a twiki

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