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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:
```mermaid
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 https://github.com/xrootd/xrootd/issues/235#issuecomment-219182669.
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:
```mermaid
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):
```mermaid
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](https://argo-mon.egi.eu/nagios/cgi-bin/extinfo.cgi?type=2&host=xrootd.phy.bris.ac.uk&service=ch.cern.WebDAV) - not sure if this is available to everyone.

Apparently, more info on that test is on a [twiki](https://twiki.cern.ch/twiki/bin/view/LCG/HTTPTFSAMProbe)


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