Check and return an error when iptables version parsing fails #69
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booxter
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Sep 3, 2019
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Ah, good catch, thanks. |
antoninbas
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Jun 26, 2020
From 0.4.1 to 0.4.5. In version 0.4.1, no error is returned by go-iptables when running `iptables --version` or parsing its ouput fails (during initialization). This leads to the library not being able to correctly detect whether the iptables version supports `--wait`, which ultimately can lead to a deadlock for the Antrea agent. See coreos/go-iptables#69. By updating the go-iptables version, we ensure that any such error will be returned to Antrea, logged, and cause the Antrea agent to fail and eventually restart. It is unclear what can cause iptables version detection to fail but because of the added logging, we will have a better shot at getting to the root cause if it happens in production again. Fixes antrea-io#871
antoninbas
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Jun 26, 2020
From 0.4.1 to 0.4.5. In version 0.4.1, no error is returned by go-iptables when running `iptables --version` or parsing its ouput fails (during initialization). This leads to the library not being able to correctly detect whether the iptables version supports `--wait`, which ultimately can lead to a deadlock for the Antrea agent. See coreos/go-iptables#69. By updating the go-iptables version, we ensure that any such error will be returned to Antrea, logged, and cause the Antrea agent to fail and eventually restart. It is unclear what can cause iptables version detection to fail but because of the added logging, we will have a better shot at getting to the root cause if it happens in production again. Fixes antrea-io#871
antoninbas
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Jun 26, 2020
From 0.4.1 to 0.4.5. In version 0.4.1, no error is returned by go-iptables when running `iptables --version` or parsing its ouput fails (during initialization). This leads to the library not being able to correctly detect whether the iptables version supports `--wait`, which ultimately can lead to a deadlock for the Antrea agent. See coreos/go-iptables#69. By updating the go-iptables version, we ensure that any such error will be returned to Antrea, logged, and cause the Antrea agent to fail and eventually restart. It is unclear what can cause iptables version detection to fail but because of the added logging, we will have a better shot at getting to the root cause if it happens in production again. Fixes antrea-io#871
antoninbas
added a commit
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Jun 26, 2020
From 0.4.1 to 0.4.5. In version 0.4.1, no error is returned by go-iptables when running `iptables --version` or parsing its ouput fails (during initialization). This leads to the library not being able to correctly detect whether the iptables version supports `--wait`, which ultimately can lead to a deadlock for the Antrea agent. See coreos/go-iptables#69. By updating the go-iptables version, we ensure that any such error will be returned to Antrea, logged, and cause the Antrea agent to fail and eventually restart. It is unclear what can cause iptables version detection to fail but because of the added logging, we will have a better shot at getting to the root cause if it happens in production again. Fixes antrea-io#871
antoninbas
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Jun 29, 2020
From 0.4.1 to 0.4.5. In version 0.4.1, no error is returned by go-iptables when running `iptables --version` or parsing its ouput fails (during initialization). This leads to the library not being able to correctly detect whether the iptables version supports `--wait`, which ultimately can lead to a deadlock for the Antrea agent. See coreos/go-iptables#69. By updating the go-iptables version, we ensure that any such error will be returned to Antrea, logged, and cause the Antrea agent to fail and eventually restart. It is unclear what can cause iptables version detection to fail but because of the added logging, we will have a better shot at getting to the root cause if it happens in production again. Fixes #871
GraysonWu
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Sep 22, 2020
From 0.4.1 to 0.4.5. In version 0.4.1, no error is returned by go-iptables when running `iptables --version` or parsing its ouput fails (during initialization). This leads to the library not being able to correctly detect whether the iptables version supports `--wait`, which ultimately can lead to a deadlock for the Antrea agent. See coreos/go-iptables#69. By updating the go-iptables version, we ensure that any such error will be returned to Antrea, logged, and cause the Antrea agent to fail and eventually restart. It is unclear what can cause iptables version detection to fail but because of the added logging, we will have a better shot at getting to the root cause if it happens in production again. Fixes antrea-io#871
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The version retrieval and parsing functions return an error which is ignored.
If the parsing fails, the version may be empty and the library may think that
--waitflag is not supported.If that flag is not supported, the library will try to lock
/var/run/xtables.lockand only after that invokeiptables, which in turn will find the file locked and return an error.This patch returns the version parsing error to the caller.
I tried to reproduce the failing part by forcing
hasWaitto false locally, not sure how can the version parsing fail but it what (I suspect) happened on kubevirt CI. More details in the issue: kubevirt/kubevirt#2660