Hello,

I understand that writing is not supported in the case of a disk-caching Proxy.

However, when attempting to write a file to the cluster through the proxy (with PFC enabled), the operation will not succeed (operation not supported) but the file is written to the local disk cache and appears to be in bad state.

Future reads for the same file will be provided from the cache, serving the corrupted file.

This can also cause confusion because although the write operation is not supported, later on, the cache can still provide that file (even if in a bad state).

Additional info

Setup: client --> proxy (with PFC) --> cluster
I am copying the hello.txt to the proxy and then reading it into hello_copied.txt.

Checksums:
bea8252ff4e80f41719ea13cdf007273 hello.txt
36df9540a5ef4996a9737657e4a8929c hello_copied.txt

File contents in hexa (ran through the xxd command):
hello.txt
0000000: 4865 6c6c 6f2c 2057 6f72 6c64 210a Hello, World!.
hello_copied.txt
0000000: 0000 0000 0000 0000 0000 0000 0000 ..............

Below are the logs from the MGM, proxy and client, as well as the proxy config.

proxy_write-client.log
proxy_write-mgm.log
proxy_write-proxy.log
xrd.cf.pss.txt

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