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Default net.ipv6.route.max_size 32768 is too low
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There are about 70k routes in the current DFZ. It's time to increase VyOS's default…? But as someone who has encountered "issues" with the potential for kernel resource exhaustion by IPv6 routes — — I would exercise caution against setting it to something inappropriate.

And maybe it's worth reconsidering whether having the humongous value of 2147483647 is sane. At least with IPv4 (and with more recent kernels for IPv6) you can't grow the routing table size without bound by scanning network address-space :)


Difficulty level
Unknown (require assessment)
Why the issue appeared?
Will be filled on close
Is it a breaking change?
Unspecified (possibly destroys the router)

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maznu created this object in space S1 VyOS Public.

@maznu , you can also set this manually set system sysctl custom net.ipv6.route.max_size value 143360, but seems default value is really small.

Agreed, I'm going to workaround with set system sysctl custom, but also submit a PR:

dmbaturin claimed this task.
dmbaturin added a project: VyOS 1.2 Crux.
erkin renamed this task from net.ipv6.route.max_size = 32768 to Default net.ipv6.route.max_size 32768 is too low.Sep 9 2020, 12:58 PM