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Subject: Re: ipv6:ping ipv6 address on the same host from the loopback
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To:     gaoxingwang <gaoxingwang1@huawei.com>, netdev@vger.kernel.org
Cc:     davem@davemloft.net, yoshfuji@linux-ipv6.org,
        chenzhen126@huawei.com, liaichun@huawei.com, yanan@huawei.com
References: <20230209134244.3953539-1-gaoxingwang1@huawei.com>
From:   David Ahern <dsahern@kernel.org>
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On 2/9/23 6:42 AM, gaoxingwang wrote:
> When I ping another ipv6 address on the same host from the loopback interface, it fails.
> Is this what was expected? Or should it work successfully like ipv4?

IMHO, ipv4 should not work; I do not recall the origins of why it does -
meaning intentional or byproduct of using the loopback device to
"transmit" packets locally.