Why I did it
Dhcpmon had incorrect RX count for server side packets. It does not raise any false alarms, but could miss catching server side packet count mismatch between snapshot and current counter.
Add debug mode which prints counter to syslog
How I did it
Due to dualtor inbound filter requirement, there are currently two filters, each for listening to rx / tx packets.
Originally, we opened up an rx/tx socket for each interface specified, which causes duplicate socket. Now we initialize the sockets only once. Both sockets are not binded to an interface, and we use vlan to interface mapping to filter packets. For inbound uplinks, we use a portchannel to interface mapping.
Previous dhcpmon counter before dual tor change:
[ Agg-Vlan1000- Current rx/tx] Discover: 1/ 4, Offer: 1/ 1, Request: 3/ 12, ACK: 1/ 1
[ eth0- Current rx/tx] Discover: 0/ 0, Offer: 0/ 0, Request: 0/ 0, ACK: 0/ 0
[ eth0- Current rx/tx] Discover: 0/ 0, Offer: 0/ 0, Request: 0/ 0, ACK: 0/ 0
[ PortChannel104- Current rx/tx] Discover: 0/ 1, Offer: 0/ 0, Request: 0/ 3, ACK: 0/ 0
[ PortChannel103- Current rx/tx] Discover: 0/ 1, Offer: 0/ 0, Request: 0/ 3, ACK: 0/ 0
[ PortChannel102- Current rx/tx] Discover: 0/ 2, Offer: 1/ 0, Request: 0/ 6, ACK: 1/ 0
[ PortChannel101- Current rx/tx] Discover: 0/ 0, Offer: 0/ 0, Request: 0/ 0, ACK: 0/ 0
[ Vlan1000- Current rx/tx] Discover: 1/ 0, Offer: 0/ 1, Request: 3/ 0, ACK: 0/ 1
[ Agg-Vlan1000- Current rx/tx] Discover: 1/ 4, Offer: 1/ 1, Request: 3/ 12, ACK: 1/ 1
Dhcpmon counter after this PR:
[ PortChannel104- Current rx/tx] Discover: 0/ 1, Offer: 0/ 0, Request: 0/ 3, ACK: 0/ 0
[ PortChannel103- Current rx/tx] Discover: 0/ 1, Offer: 0/ 0, Request: 0/ 3, ACK: 0/ 0
[ PortChannel102- Current rx/tx] Discover: 0/ 2, Offer: 1/ 0, Request: 0/ 6, ACK: 1/ 0
[ PortChannel101- Current rx/tx] Discover: 0/ 0, Offer: 0/ 0, Request: 0/ 0, ACK: 0/ 0
[ Vlan1000- Current rx/tx] Discover: 1/ 0, Offer: 0/ 1, Request: 3/ 0, ACK: 0/ 1
[ Agg-Vlan1000- Current rx/tx] Discover: 1/ 4, Offer: 1/ 1, Request: 3/ 12, ACK: 1/ 1
How to verify it
Ran dhcp relay test to send all four packets in singles and batches on both single ToR and dual ToR. Counter was as expected.
Why I did it
Fix issue caused by dualtor support PR [dhcpmon] Open different socket for dual tor to enable interface filtering #11201
Improve code
How I did it
On single ToR, packets received count was duplicated due to socket filter set to "inbound"
Tx count not increasing due to filter set to "inbound". Added an outbound socket to count tx packets
Added vlan member interface mapping for Ethernet interface to vlan interface lookup in reference to PR Fix multiple vlan issue sonic-dhcp-relay#27
Exit when socket fails to initialize to allow dhcp_relay docker to restart
How to verify it
Tested on vstestbed single tor and dual tor, sent packets and verify printed out dhcpmon rx and tx counters is correct
Correct number of tx increases
Tx does not increase when ToR is on standby
Why I did it
Revert change in syslog such that it does not utilize c++ string
How I did it
Code change
How to verify it
Which release branch to backport (provide reason below if selected)
201811
201911
202006
202012
202106
202111
202205
Description for the changelog
Ensure to add label/tag for the feature raised. example - PR#2174 under sonic-utilities repo. where, Generic Config and Update feature has been labelled as GCU.
Link to config_db schema for YANG module changes
A picture of a cute animal (not mandatory but encouraged)
Enable dbgsym package for dhcpmon.
Allow CFLAGS and LDFLAGS from environment variables to be used
in the dhcp6relay build. This makes sure that the -O2 flag from
dpkg-buildflags gets used.
Finally, enable all hardening flags in dpkg-buildflags for
dhcp6relay and dhcpmon. The change from the default set of flags is that
during linking, immediate binding of symbols is done instead of lazy
binding.
Signed-off-by: Saikrishna Arcot <sarcot@microsoft.com>
As part of this, update the isc-dhcp package to match the Bullseye
version (this fixes some compile errors related to BIND), clean up some
of the build dependencies and runtime dependencies for debian packaging,
and use the default Boost version to compile against instead of
explicitly saying using 1.74.
Signed-off-by: Saikrishna Arcot <sarcot@microsoft.com>
#### Why I did it
Enhance DHCP monitor application following the implementation PR: https://github.com/Azure/sonic-buildimage/pull/7772
#### How I did it
Add the support for monitoring DHCPv6 packets.
#### How to verify it
Install an image with this PR and the implementation PR.
Printing both snapshot and current counter sets will make it easier to pinpoint
which message type(s) is/are not being relayed. This PR prints both counter sets.
Also, this PR defines gnu11 as a C standard to compile with in order to avoid
making changes when porting to 201811 branch.
singed-off-by: Tamer Ahmed <tamer.ahmed@microsoft.com>
When BGP routes are missing, DHCP packets get relayed over mgmt
interface. This results in dhcpmon alerting that DHCP packets are
not being relayed. This is PR include mgmt interface as uplink
device, and so, if DHCP packet gets relayed over mgmt interface,
regular dhcpmon alert will not be issues. Instead, dhcpmon will
check the mgmt interface counts and issue a separate alert regarding
packets travelling through mgmt network.
In addition, this PR includes the following enhancements:
1. Add SIGUSR1 handler that prints out current packet counts
2. Increase alert grace window to 3 minutes from currently 2 minutes
3. Time is now computed more accurately
4. Print vlan name before counters
signed-off-by: Tamer Ahmed <tamer.ahmed@microsoft.com>
- Add .gitignore files in each subdirectory of src/, so as to reduce the size of the .gitignore file in the project root, and also make it easier to maintain (i.e., if a directory in src/ is removed, there will not be outdated entries in the root .gitignore file.
- Also add missing .gitignore entries and remove outdated entries and duplicates.
* [dhcpmon] Filter DHCP O/A Messages of Neighboring Vlans
This code fixes a bug where two or more vlans exist. Cross contamination
happens for DHCP packets Offer/Ack when received on shared northbound links.
The code filters out those packet based on dst IP equal Vlan loopback IP.
signed-off-by: Tamer Ahmed <tamer.ahmed@microsoft.com>
DHCP relay MONitor (dhcpmon) keeps track of DORA messages. If DHCP Relay
is detected to be not forwarding DORA message, dhcpmon will log such event
to syslog. Under the hood dhcpmon keeps counts of clients DR messages,
forwarded DR messages, DHCP server OA messages, and forwarded OA messages.
dhcpmon will check every 12 sec (configurable) if counts are monotonically
increasing and record snapshot of those counters. dhcpmon will report
discrepancies when detected between current counters and snapshot counters.
pull-request: https://github.com/Azure/sonic-buildimage/pull/3886
signed-off-by: Tamer Ahmed <tamer.ahmed@microsoft.com>
