Traditionally, the MTU in "datagram" transport mode was restricted to
2044. That is no longer the case, relax that.
In fact, choose a very large maximum and don't differenciate between
"connected" mode (they now both use now 65520). This is only the
limitation of the connection profile. Whether setting such large MTUs
actually works must be determined when activating the profile.
Initscripts "ifup-ib" from rdma-core package originally had a limit of 2044.
This was raised to 4092 in rh#1186498. It is suggested to raise it further
in bug rh#1647541.
In general, kernel often does not allow setting large MTUs. And even if it
allows it, it may not work because it also requires the entire network to
be configured accordingly. But that means, it is generally not helpful to
limit the MTU in the connection profile too strictly. Just allow large
MTUs, we need to see at activation time whether the configuration works.
Note also that all other setting types don't validate the range for MTU at
all.
Related: https://bugzilla.redhat.com/show_bug.cgi?id=1186498
Related: https://bugzilla.redhat.com/show_bug.cgi?id=1593334
(rdma-core: raise limit from 2044 to 4092 in ifup-ib)
Related: https://bugzilla.redhat.com/show_bug.cgi?id=1647541
(rdma-core: raise limit beyond 4092 in ifup-ib)
Related: https://bugzilla.redhat.com/show_bug.cgi?id=1532638#c4
(rdma-core: MTU related discussion)
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1534869
(NetworkManager bug about this topic, but with lots of unrelated
discussion. See in particular #c16)
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1653494
Add NMIPRoutingRule API with a few basic rule properties. More
properties will be added later as we want to support them.
Also, add to/from functions for string/GVariant representations.
These will be needed to persist/load/exchange rules.
The to-string format follows the `ip rule add` syntax, with the aim
to be partially compatible. Full compatibility is not possible though,
for various reasons (see code comment).
Part 1, which addresses the issue for simple properties that have
a plain remove-by-value function.
Rationale:
Removing a value/index that does not exist should not be a failure.
Woule you like:
$ nmcli connection modify "$PROFILE" autoconnect no
$ nmcli connection modify "$PROFILE" autoconnect no
Error: autoconnect is already disabled
So, why would it be a good idea to fail during
$ nmcli connection modify "$PROFILE" -vpn.data ca
$ nmcli connection modify "$PROFILE" -vpn.data ca
Error: failed to remove a value from vpn.data: invalid option 'ca'.
Generally, it should not be an error to remove an option, as long
as the option itself is valid. For example,
$ nmcli connection modify "$PROFILE" -vlan.ingress-priority-map bogus
should fail, but
$ nmcli connection modify "$PROFILE" -vlan.ingress-priority-map 1:5
should succeed even if there was nothing to remove.
The same code is used by nmcli. Obviously, clients also need to
parse string representations.
That begs the question whether this should be public API of libnm.
Maybe, but don't decide that now, just reuse the code internally via
"shared/nm-libnm-core-utils.h".
We have code in "shared/nm-utils" which are general purpose
helpers, independent of "libnm", "libnm-core", "clients" and "src".
We have shared code like "shared/nm-ethtool-utils.h" and
"shared/nm-meta-setting.h", which is statically linked, shared
code that contains libnm related helpers. But these helpers already
have a specific use (e.g. they are related to ethtool or NMSetting
metadata).
Add a general purpose helper that:
- depends (and extends) libnm-core
- contains unrelated helpers
- can be shared (meaning it will be statically linked).
- this code can be used by any library user of "libnm.so"
(nmcli, nm-applet) and by "libnm-core" itself. Thus, "src/"
and "libnm/" may also use this code indirectly, via "libnm-core/".
