AWS: fix routes for ngw in subnets

[ratulm]

No description provided.

[batfish-bot]

This change is 

[dhalperi]

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projects/batfish/src/main/java/org/batfish/representation/aws/Subnet.java, line 650 at r1 (raw file):

            // instead of ignoring it because it is the correct model and users expect routes in AWS
            // and Batfish to line up.
            nexthopInterfaceName = instancesInterfaceName(_subnetId);

Hmm. IIUC we usually send packets between two nodes communicating in the same subnet p2p -- e.g., instances send directly to each other instead of through subnet node, right? Didn't we run into problems with filtering otherwise?

[dhalperi]

Reviewable status: 0 of 2 files reviewed, 2 unresolved discussions (waiting on @dhalperi, @progwriter, and @ratulm)

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projects/batfish/src/main/java/org/batfish/representation/aws/Subnet.java, line 643 at r1 (raw file):

send it directly.

update comment?

[dhalperi]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @dhalperi, @progwriter, and @ratulm)

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projects/batfish/src/main/java/org/batfish/representation/aws/Subnet.java, line 650 at r1 (raw file):

Previously, dhalperi (Dan Halperin) wrote…

Hmm. IIUC we usually send packets between two nodes communicating in the same subnet p2p -- e.g., instances send directly to each other instead of through subnet node, right? Didn't we run into problems with filtering otherwise?

nm, I misunderstood the context. What was happening before? Did that next hop interface not exist?

[codecov]

Codecov Report

Merging #6263 into master will decrease coverage by 0.01%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##             master    #6263      +/-   ##
============================================
- Coverage     72.90%   72.89%   -0.02%     
+ Complexity    35006    34998       -8     
============================================
  Files          2832     2832              
  Lines        142258   142256       -2     
  Branches      17082    17082              
============================================
- Hits         103714   103695      -19     
- Misses        30319    30331      +12     
- Partials       8225     8230       +5     

Impacted Files	Coverage Δ	Complexity Δ
...in/java/org/batfish/representation/aws/Subnet.java	84.32% <100.00%> (+1.20%)	69.00 <0.00> (+1.00)
...g/batfish/datamodel/flow/IncomingSessionScope.java	84.61% <0.00%> (-15.39%)	7.00% <0.00%> (-1.00%)
...src/main/java/org/batfish/coordinator/PoolMgr.java	54.32% <0.00%> (-6.18%)	13.00% <0.00%> (-3.00%)
...col/src/main/java/org/batfish/role/InferRoles.java	89.54% <0.00%> (-1.37%)	50.00% <0.00%> (-1.00%)
...src/main/java/org/batfish/coordinator/WorkMgr.java	75.38% <0.00%> (-0.78%)	244.00% <0.00%> (-3.00%)
...ain/java/org/batfish/coordinator/WorkQueueMgr.java	70.93% <0.00%> (-0.59%)	90.00% <0.00%> (-1.00%)
...a/org/batfish/representation/aws/LoadBalancer.java	82.18% <0.00%> (-0.32%)	70.00% <0.00%> (-1.00%)
...tfish/representation/cisco/CiscoConfiguration.java	85.91% <0.00%> (-0.14%)	492.00% <0.00%> (-1.00%)
...g/batfish/dataplane/ibdp/IncrementalBdpEngine.java	90.77% <0.00%> (-0.02%)	75.00% <0.00%> (ø%)
... and 3 more

[ratulm]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @dhalperi and @progwriter)

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projects/batfish/src/main/java/org/batfish/representation/aws/Subnet.java, line 650 at r1 (raw file):

Previously, dhalperi (Dan Halperin) wrote…

nm, I misunderstood the context. What was happening before? Did that next hop interface not exist?

yeah, the wrong interface name was being used, so the route was not getting wiped out.

[dhalperi]

Reviewed 2 of 2 files at r1.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @progwriter)

[ratulm]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @progwriter)

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projects/batfish/src/main/java/org/batfish/representation/aws/Subnet.java, line 650 at r1 (raw file):

Previously, ratulm wrote…

yeah, the wrong interface name was being used, so the route was not getting wiped out.

was getting wiped out