Rpc.xdaichain.com sometimes returns duplicate cors headers

Support
#1

On zeroalpha.art we’re seeing occasional failures of requests to https://rpc.xdaichain.com/ :

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The response for a failed request:

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You can see that the field access-control-allow-origin is indeed set twice.

The request looked like this:

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This is something which seems to happen randomly.
The same request usually succeeds (the site polls the state every 5 seconds) - with the response containing only one access-control-allow-origin field (with value set to*).
It looks as if the request is handled by various instances behind a load balancer which behave slightly differently.

1 Like
#2

Thanks for reporting. We deployed a fix and run the page for a few minutes. No errors so far.

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Please let us know if the problem is not fixed on your end.

P.S. Someone just purchased the item…

#3

great, thx!
Btw. may it be that the xdai RPC nodes have no min gas price set? Thomas had a tx accepted, but not executed (gas price set to < 1 gwei). If it’s the OpenEthereum client, I suggest to set min_gas_price=1000000000 in the RPC node config.

#4

thanks, btw it’s --min-gas-price=1000000000
but it’s a good question what is the right setting here. some transactions are accepted with 0 GWei, e.g. some system transactions or transactions with transaction priority https://www.xdaichain.com/for-validators/for-consensus-validators/transactions-prioritization-in-aura

#5

ah, didn’t know that there’s 0 gwei txs which go through the public RPC. Then it’s probably a UX tradeoff to be made.