[TEMP][dhcpmon] Validate Fungible F2 repair stack by Xichen96 · Pull Request #94 · sonic-net/sonic-dhcpmon

Xichen96 · 2026-07-25T21:26:48Z

Description of PR

Temporary CI/hardware validation stack for the Fungible F2 dhcpmon repairs.
Do not review or merge this PR.

Included signed commits:

[dhcpmon] Track PortChannels under downstream VLANs #89 - nested
PortChannel/VLAN hierarchy.
[dhcpmon] Make relay disparity detection resilient #90 - reliable disparity
detection.
[dhcpmon] Add packet event quiescing #91 - packet-event
quiescing.
[dhcpmon] Reconcile runtime membership state #92 - transactional
topology/counter reconciliation.
[dhcpmon] Listen for membership updates #93 - CONFIG_DB membership
listener.

The conflict resolution preserves PR #89's single-ToR
Ethernet -> PortChannel -> VLAN mapping while making PR #92's map rebuild
transactional.

Work item tracking

Microsoft ADO (number only): 38615412

Type of change

Bug fix

Approach

What is the motivation for this PR?

Produce one Azure-CI-built dhcpmon artifact containing the exact final repair
stack for regular BJW and Fungible F2 hardware validation.

How did you do it?

Cherry-pick the five focused signed commits onto current master and resolve
only their expected integration overlap.

How did you verify/test it?

Pending Azure PR CI and hardware validation.

Any platform specific information?

No.

Back port request

None.

Tested branch

Pending.

Test result

Pending.

Documentation

Not applicable.

mssonicbld · 2026-07-25T21:26:56Z

/azp run

azure-pipelines · 2026-07-25T21:26:56Z

Azure Pipelines: There may be pipelines that require an authorized user to comment /azp run to run.

azure-pipelines · 2026-07-25T21:27:05Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Copilot

Pull request overview

Temporary validation stack for dhcpmon “repair” commits targeting Fungible F2 and related topology/health-check correctness. The changes add runtime membership refresh and transactional counter/topology reconciliation while improving relay-disparity robustness and packet-event handling during refresh.

Changes:

Add CONFIG_DB membership subscribers (VLAN_MEMBER / PORTCHANNEL_MEMBER) and main-thread topology reconciliation with packet-handler quiescing.
Make relay-disparity detection more resilient (watermarks / grace window / episode reporting latch).
Improve socket/event infrastructure (event suspend/resume, keepalive event, bounded packet processing per callback) and update aggregate-counter parent resolution.

Reviewed changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/util.h	Removes legacy aggregate-counter helper (replaced by devman helper).
src/sock_mgr.h	Adds packet-handler suspend/resume and cache-counter pruning API.
src/sock_mgr.cpp	Implements keepalive event, suspend/resume, and cache-counter pruning.
src/packet_handler.cpp	Uses devman aggregate-counter naming and bounds packets processed per callback.
src/health_check.h	Adds per-check “reported” latch state.
src/health_check.cpp	Latches unhealthy episode reporting and resets latch on healthy.
src/event_mgr.h	Adds suspend/resume APIs for tagged event groups.
src/event_mgr.cpp	Implements suspend/resume; fixes fd logging after event_free.
src/dhcp_mon.h	Adds `dhcp_mon_reconcile_topology()` public API.
src/dhcp_mon.cpp	Adds CONFIG_DB subscriber events, transactional mapping/counter reconciliation, and refresh flow in health timer.
src/dhcp_devman.h	Adds transactional mapping refresh + parent/aggregate helper APIs.
src/dhcp_devman.cpp	Implements transactional mapping rebuild and parent/aggregate resolution for nested topologies.
src/dhcp_device.h	Adds API to reset relay health watermarks to current counters.
src/dhcp_device.cpp	Implements watermark-based disparity detection with grace window and state tracking.

mssonicbld · 2026-07-25T22:43:17Z

/azp run

azure-pipelines · 2026-07-25T22:43:27Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Copilot

Pull request overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (3)

src/sock_mgr.cpp:468

sock is unused in this structured binding loop, which will warn under -Wall. Rewrite the loop to avoid binding an unused variable.

int sock_mgr_resume_packet_handler()
{
    for (const auto &[sock, info] : sock_map) {
        if (info.event_mgr_ptr->resume_all_events(packet_handler_tag) < 0) {
            sock_mgr_suspend_packet_handler();
            return -1;
        }
    }
    return 0;
}

src/dhcp_device.cpp:104

dhcp_device_reset_health_state(ifname) clears relay_flow_states for all interfaces/sockets, even though the API name/docs imply an interface-scoped reset. This can unintentionally drop pending relay-disparity state for other interfaces. Prefer erasing only the entry for the requested interface.

void dhcp_device_reset_health_state(const std::string &ifname)
{
    std::lock_guard<std::mutex> lock(relay_flow_state_mutex);
    relay_flow_states.clear();
    initialize_relay_flow_states(ifname, rx_sock, tx_sock,
                                 (const int *)monitored_msgs, monitored_msg_sz);
}

src/dhcp_mon.cpp:484

If sock_mgr_resume_packet_handler() fails, sock_mgr_resume_packet_handler() has already suspended packet events (it calls sock_mgr_suspend_packet_handler() on failure). Returning here leaves the daemon running with packet processing permanently disabled. Consider terminating to allow a supervisor restart, or implement an explicit recovery path.

    if (topology_refresh_pending) {
        sock_mgr_suspend_packet_handler();
        int result = dhcp_mon_reconcile_topology();
        if (sock_mgr_resume_packet_handler() < 0) {
            syslog(LOG_ALERT, "Failed to resume packet handlers after topology refresh");
            return;
        }

Resolve nested Ethernet-to-PortChannel-to-VLAN membership and aggregate counters at each immediate parent without changing existing Dual-ToR attribution. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Track DHCPv4 disparity per message type with absolute watermarks, adjacent-window TX credit, main-loop clear reset, and one report per persistent outage; disable the invalid DHCPv6 same-type signal. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Allow packet handlers to be suspended and resumed without terminating socket event loops, and bound each callback batch so quiescing completes under sustained traffic. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Rebuild membership maps transactionally and reconcile cache and COUNTERS_DB state while preserving unchanged interface counters and rolling back failures. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Register VLAN_MEMBER and PORTCHANNEL_MEMBER subscriber file descriptors on the main event loop and apply quiesced transactional refreshes without restarting dhcpmon. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

mssonicbld · 2026-07-25T22:52:58Z

/azp run

azure-pipelines · 2026-07-25T22:53:07Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Reset only the requested interface, include direct container dependencies, and label the alert as DHCPv4-only. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Reset sockaddr length for each batch receive and reject timeout events from the fd-only resume path. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Continue checking the last topology while counter clear or subscriber recovery delays a pending refresh. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

mssonicbld · 2026-07-25T23:20:50Z

/azp run

azure-pipelines · 2026-07-25T23:20:59Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Copilot

Pull request overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated 3 comments.

Treat a self-mapped VLAN or PortChannel member as a root interface instead of creating a self aggregate. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Copilot

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Validate snapshot socket keys before looking up metadata so malformed or stale caller data cannot throw from sock_map.at(). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Reconcile current and snapshot counter maps independently so operator[]-created snapshot entries cannot survive after an interface leaves the tracked topology. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Drain raw socket receive buffers while packet handlers remain suspended after a successful topology commit, preventing pre-change packets from being attributed with new mappings. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

mssonicbld · 2026-07-26T04:21:32Z

/azp run

azure-pipelines · 2026-07-26T04:21:42Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Copilot

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

+    uint64_t last_rx;
+    uint64_t last_tx;
+    uint32_t pending_windows;
+    uint8_t tx_credit;
+    bool initialized;


Include family, direction, parent and child-aggregate deltas, expected ratio, and message type in persistent hierarchy mismatch logs for precise loss localization. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

mssonicbld · 2026-07-26T05:20:39Z

/azp run

azure-pipelines · 2026-07-26T05:20:49Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Copilot

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated no new comments.

Reject non-resumable event tags before deletion, roll back partial event_del failures, and surface suspend errors through the socket manager for coherent fail-stop recovery. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

mssonicbld · 2026-07-26T05:51:43Z

/azp run

azure-pipelines · 2026-07-26T05:51:53Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Copilot

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

+    std::vector<struct event *> deleted_events;
+    for (const auto &event : tagged_events->second) {
+        if (event_del(event) < 0) {
+            bool restore_failed = false;
+            for (struct event *deleted_event : deleted_events) {
+                if (event_add(deleted_event, NULL) < 0) {
+                    restore_failed = true;
+                }
+            }
+            syslog(LOG_ALERT, "event_mgr: Failed to suspend event (fd=%d) with tag %s for %s",
+                   event_get_fd(event), tag.c_str(), this->name.c_str());
+            return restore_failed ? -2 : -1;
+        }
+        deleted_events.push_back(event);
+    }
+    return 0;


Evaluate both an interface and its immediate-child aggregate before declaring a quiet window, so child-only packet observations expose the exact forwarding edge that did not advance. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

mssonicbld · 2026-07-26T06:08:54Z

/azp run

azure-pipelines · 2026-07-26T06:09:03Z

Azure Pipelines: Successfully started running 1 pipeline(s).

Copilot

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated no new comments.

Xichen96 · 2026-07-26T06:24:31Z

Temporary validation stack is complete. Regular master regression and F2 hardware evidence were captured; this PR must not merge. Focused fixes remain in the component PRs.

Copilot AI review requested due to automatic review settings July 25, 2026 21:26

Copilot started reviewing on behalf of Xichen96 July 25, 2026 21:27 View session

Copilot AI reviewed Jul 25, 2026

View reviewed changes

Comment thread src/dhcp_device.cpp

Comment thread src/dhcp_mon.cpp

Copilot AI review requested due to automatic review settings July 25, 2026 22:43

Xichen96 force-pushed the dev/xichenlin/validate-f2-repair-stack branch from 1ba370a to e7ef03c Compare July 25, 2026 22:43

Copilot started reviewing on behalf of Xichen96 July 25, 2026 22:43 View session

Copilot AI reviewed Jul 25, 2026

View reviewed changes

Comment thread src/sock_mgr.cpp Outdated

Comment thread src/sock_mgr.cpp

Comment thread src/dhcp_mon.cpp Outdated

Xichen96 added 5 commits July 25, 2026 22:49

Xichen96 force-pushed the dev/xichenlin/validate-f2-repair-stack branch from e7ef03c to 93a2631 Compare July 25, 2026 22:52

Xichen96 added 4 commits July 25, 2026 23:18

[dhcpmon]: Fix aggregate comment typo

646cdb2

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 39f979be-d826-4d5c-949a-f20abb58bb83 Signed-off-by: Xichen96 <lukelin0907@gmail.com>

Copilot AI review requested due to automatic review settings July 25, 2026 23:20

Copilot started reviewing on behalf of Xichen96 July 25, 2026 23:21 View session

Copilot AI reviewed Jul 25, 2026

View reviewed changes

Comment thread src/dhcp_mon.cpp

Comment thread src/sock_mgr.cpp Outdated

Comment thread src/dhcp_mon.cpp

Copilot AI reviewed Jul 26, 2026

View reviewed changes

Comment thread src/dhcp_mon.cpp

Xichen96 added 3 commits July 26, 2026 14:19

Copilot AI review requested due to automatic review settings July 26, 2026 04:21

Copilot started reviewing on behalf of Xichen96 July 26, 2026 04:21 View session

Copilot AI reviewed Jul 26, 2026

View reviewed changes

Comment thread src/dhcp_device.cpp

Comment on lines +77 to +81

uint64_t last_rx;

uint64_t last_tx;

uint32_t pending_windows;

uint8_t tx_credit;

bool initialized;

Copilot AI review requested due to automatic review settings July 26, 2026 05:20

Copilot started reviewing on behalf of Xichen96 July 26, 2026 05:21 View session

Copilot AI reviewed Jul 26, 2026

View reviewed changes

Copilot AI review requested due to automatic review settings July 26, 2026 05:51

Copilot started reviewing on behalf of Xichen96 July 26, 2026 05:52 View session

Copilot AI reviewed Jul 26, 2026

View reviewed changes

Copilot AI review requested due to automatic review settings July 26, 2026 06:08

Copilot started reviewing on behalf of Xichen96 July 26, 2026 06:09 View session

Copilot AI reviewed Jul 26, 2026

View reviewed changes

Xichen96 closed this Jul 26, 2026

Xichen96 deleted the dev/xichenlin/validate-f2-repair-stack branch July 26, 2026 06:24

Uh oh!

Conversation

Xichen96 commented Jul 25, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Description of PR

Work item tracking

Type of change

Approach

What is the motivation for this PR?

How did you do it?

How did you verify/test it?

Any platform specific information?

Back port request

Tested branch

Test result

Documentation

Uh oh!

mssonicbld commented Jul 25, 2026

Uh oh!

azure-pipelines Bot commented Jul 25, 2026

Uh oh!

azure-pipelines Bot commented Jul 25, 2026

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

Uh oh!

Uh oh!

mssonicbld commented Jul 25, 2026

Uh oh!

azure-pipelines Bot commented Jul 25, 2026

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

Uh oh!

Uh oh!

Uh oh!

mssonicbld commented Jul 25, 2026

Uh oh!

azure-pipelines Bot commented Jul 25, 2026

Uh oh!

mssonicbld commented Jul 25, 2026

Uh oh!

azure-pipelines Bot commented Jul 25, 2026

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

Uh oh!

mssonicbld commented Jul 26, 2026

Uh oh!

azure-pipelines Bot commented Jul 26, 2026

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

mssonicbld commented Jul 26, 2026

Uh oh!

azure-pipelines Bot commented Jul 26, 2026

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Uh oh!

mssonicbld commented Jul 26, 2026

Uh oh!

azure-pipelines Bot commented Jul 26, 2026

Xichen96 commented Jul 25, 2026 •

edited

Loading