When an IS-IS interface is coming down, fast-reroute may be triggered
twice: a first time after the detection of the interface down event and
a second time after the detection of the adjacency down (because of the
expiration of the ISIS Hello or BFD timers).
Avoid a BFD down event from running fast-reroute another time if the
interface was already detected down.
Signed-off-by: Louis Scalbert <louis.scalbert@6wind.com>
When a adjacency falls down, the primary routes are not deleted on the
dataplane until the SPF is recomputed. Even the backup routes are
pre-installed on the dataplane, there is no fast-route optimization.
Reasons for an adjacency to come down are:
- BFD down
- Hello timer timeout
- User adjacency clear
Apply the backup route switchover for fast-reroute as soon an IS-IS
adjacency falls down before the first SPF re-computation. Pre-computed
backup routes are applied sooner.
Signed-off-by: Louis Scalbert <louis.scalbert@6wind.com>
We don't need to scan through all configured areas to find the circuit
associated with the interface. It is always stored in ifp->info.
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Currently, we have a lot of checks in CLI and NB layer to prevent
incompatible IS-types of circuits and areas. All these checks become
completely meaningless when the interface is moved between VRFs. If the
area IS-type is different in the new VRF, previously done checks mean
nothing and we still end up with incorrect circuit IS type. To actually
prevent incorrect IS type, all checks must be done in the processing
code.
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
The current implementation of TI-LFA computes link-protecting
repair paths (even when node protection is enabled) to have repair
paths to all destinations when no node-protecting repair has been
found. This may be desired or not. E.g. the link-protecting paths
may use the protected node and be, therefore, useless if the node
fails. Also, computing link-protecting repairs incurs extra
calculations.
With this patch, when node protection is enabled, link protecting
repair paths are only computed if "link-fallback" is specified in
the configuration, on a per interface and IS-IS level.
Signed-off-by: Fredi Raspall <fredi@voltanet.io>
Currently we don't allow to configure the interface before the area is
configured. This approach has the following issues:
1. The area config can be deleted even when we have an interface config
relying on it. The code is not ready for that - we'll have a whole
bunch of stale pointers if user does that.
2. The code doesn't correctly process the event of changing the VRF for
an interface. There is no mechanism to ensure that the area exists
in the new VRF so currently the circuit still stays in the old VRF.
This commit allows an arbitrary order of area/interface configuration.
There is no more need to configure the area before configuring the
interface.
This change fixes both the issues.
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Necessary structures for snmp-id generation are currently stored in
`struct isis`. When we generate the new circuit ID, we always use the
instance from the default VRF. When we free the circuit ID, we use the
instance from the circuit VRF. This causes the following problems:
1. If there is no instance in the default VRF, this code doesn't work.
2. When circuit in non-default VRF is deleted, the ID is not actually
freed.
This is fixed by using global structures instead. The code itself is
moved to isis_snmp.c and linked to the main code using hooks. We should
not call SNMP-related code when the SNMP module is not loaded at all.
More than that, we don't allow to activate the circuit if we failed to
generate the SNMP ID. Even if SNMP support is completely disabled! This
check is removed.
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Add support for read only mib objects from RFC4444.
Signed-off-by: Lynne Morrison <lynne@voltanet.io>
Signed-off-by: Karen Schoener <karen@voltanet.io>
Remote LFA (RFC 7490) is an extension to the base LFA mechanism
that uses dynamically determined tunnels to extend the IP-FRR
protection coverage.
RLFA is similar to TI-LFA in that it computes a post-convergence
SPT (with the protected interface pruned from the network topology)
and the P/Q spaces based on that SPT. There are a few differences
however:
* RLFAs can push at most one label, so the P/Q spaces need to
intersect otherwise the destination can't be protected (the
protection coverage is topology dependent).
* isisd needs to interface with ldpd to obtain the labels it needs to
create a tunnel to the PQ node. That interaction needs to be done
asynchronously to prevent blocking the daemon for too long. With
TI-LFA all required labels are already available in the LSPDB.
RLFA and TI-LFA have more similarities than differences though,
and thanks to that both features share a lot of code.
Limitations:
* Only RLFA link protection is implemented. The algorithm used
to find node-protecting RLFAs (RFC 8102) is too CPU intensive and
doesn't always work. Most vendors implement RLFA link protection
only.
* RFC 7490 says it should be a local matter whether the repair path
selection policy favors LFA repairs over RLFA repairs. It might be
desirable, for instance, to prefer RLFAs that satisfy the downstream
condition over LFAs that don't. In this implementation, however,
RLFAs are only computed for destinations that can't be protected
by local LFAs.
Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
TI-LFA is a modern fast-reroute (FRR) solution that leverages Segment
Routing to pre-compute backup nexthops for all destinations in the
network, helping to reduce traffic restoration times whenever a
failure occurs. The backup nexthops are expected to be installed
in the FIB so that they can be activated as soon as a failure
is detected, making sub-50ms recovery possible (assuming an
hierarchical FIB).
TI-LFA is a huge step forward compared to prior IP-FRR solutions,
like classic LFA and Remote LFA, as it guarantees 100% coverage
for all destinations. This is possible thanks to the source routing
capabilities of SR, which allows the backup nexthops to steer traffic
around the failures (using as many SIDs as necessary). In addition
to that, the repair paths always follow the post-convergence SPF
tree, which prevents transient congestions and suboptimal routing
from happening.
Deploying TI-LFA is very simple as it only requires a single
configuration command for each interface that needs to be protected
(both link protection and node protection are available). In addition
to IPv4 and IPv6 routes, SR Prefix-SIDs and Adj-SIDs are also
protected by the backup nexthops computed by the TI-LFA algorithms.
Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
There are code paths where we were not always setting the
circuit->isis on creation. Fix that up so it will always
happen.
Signed-off-by: Donald Sharp <sharpd@nvidia.com>
Lookup in C_STATE_NA must be made before the new circuit creation, or it
will be leaked if the isis instance is not found. All other lookups are
unnecessary - we just need to remember the previously used instance.
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Since this command is modeled using YANG, it's already displayed
as part of the call to nb_cli_show_dnode_cmds(). Calling the
'isis_circuit_config_write' hook was only making that command
to be displayed twice.
The aforementioned hook is still necessary for fabricd, which wasn't
converted to the new northbound model yet.
Fixes#6281.
Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
The new "event-counters" grouping is almost a 1:1 copy of the same
grouping from the IETF IS-IS module, except for the "lan-dis-changes"
leaf which was skipped (more work needs to be done to support it).
Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
Switch the zclient->interface_add functionality to have everyone
use the interface create callback in lib/if.c
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
In preparation to Segment Routing:
- Update the management of Traffic Engineering subTLVs to the new tlvs parser
- Add Router Capability TLV 242 as per RFC 4971 & 7981
- Add Segment Routing subTLVs as per draft-isis-segment-routing-extension-25
Modified files:
- isis_tlvs.h: add new structure to manage TE subTLVs, TLV 242 & SR subTLVs
- isis_tlvs.c: add new functions (pack, copy, free, unpack & print) to process
TE subTLVs, Router Capability TLV and SR subTLVs
- isis_circuit.[c,h] & isis_lsp.[c,h]: update to new subTLVs & TLV processing
- isis_te.[c,h]: remove all old TE structures and managment functions,
and add hook call to set local and remote IP addresses as wellas update TE
parameters
- isis_zebra.[c,h]: add hook call when new interface is up
- isis_mt.[c,h], isis_pdu.c & isis_northbound.c: adjust to new TE subTLVs
- tests/isisd/test_fuzz_isis_tlv_tests.h.gz: adapte fuuz tests to new parser
Signed-off-by: Olivier Dugeon <olivier.dugeon@orange.com>
Solve issue #4032
- Change MPLS-TE from global to per Area
- Add new mpls_te_area structure to area in replacement of global variable
isisMPLS_TE
- Move mpls-te from global to instance in frr-isisd.yang
- Change code in isis_te.c, isis_northbound.c, isis_cli.c, isis_pdu.c,
isis_lsp.c and isis_zebra.c accordingly
Signed-off-by: Olivier Dugeon <olivier.dugeon@orange.com>
- Change MPLS-TE from global to per Area
- Add new mpls_te_area structure to area in replacement of global variable
isisMPLS_TE
- Move mpls-te frmo global to instance in frr-isisd.yang
- Change code in isis_te.c, isis_northbound.c, isis_cli.c, isis_pdu.c,
isis_lsp.c and isis_zebra.c accordingly
Signed-off-by: Olivier Dugeon <olivier.dugeon@orange.com>
remove the return value and redundant validations from
isis_circuit_circ_type_set(), since they are no longer needed.
Signed-off-by: Emanuele Di Pascale <emanuele@voltanet.io>
Before this commit, isisd/fabricd maintained a bitfield for each LSP
to track the SRM bit for each circuit, which specifies whether an LSP
needs to be sent on that circuit. Every second, it would scan over all
LSPs in `lsp_tick` and queue them up for transmission accordingly.
This design has two drawbacks: a) it scales poorly b) it adds
unacceptable latency to the update process: each router takes a random
amount of time between 0 and 1 seconds to forward an update. In a
network with a diamter of 10, it might already take 10 seconds for an
update to traverse the network.
To mitigate this, a new design was chosen. Instead of tracking SRM in a
bitfield, have one tx_queue per circuit and declare that an LSP is in
that queue if and only if it would have SRM set for that circuit.
This way, we can track SRM similarly as we did before, however, on
insertion into the LSP queue, we can add a timer for (re)transmission,
alleviating the need for a periodic scan with LSP tick and reducing the
latency for forwarding of updates.
Signed-off-by: Christian Franke <chris@opensourcerouting.org>
Remove isis_vty.c and create three new files isis_vty_common.c,
isis_vty_fabricd.c and isis_vty_isisd.c which are built into both
daemons, only fabricd and only isisd, respectively.
Signed-off-by: Christian Franke <chris@opensourcerouting.org>
The following types are nonstandard:
- u_char
- u_short
- u_int
- u_long
- u_int8_t
- u_int16_t
- u_int32_t
Replace them with the C99 standard types:
- uint8_t
- unsigned short
- unsigned int
- unsigned long
- uint8_t
- uint16_t
- uint32_t
Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>
Add a timestamp information for level 2 circuits, otherwise if the
circuit is marked as already processed on level 1 we will not process
level 2 areas.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>