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AnyConnect Secure Client OSPF neighbor stuck 2WAY broadcast DR election: Fix

By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-30

I keep coming back to this exact symptom on the ASR-1002-HX, so I finally wrote it down properly. Monday morning I was on a video call with Anita, head of infra at a Tier-3 colo in Outer Ring Road, Bengaluru, and we needed to fix neighbour glued at 2-WAY across the broadcast segment before the 9 AM trading window. We did. This page is what I wish I had had open when the ticket landed.

If you came in from a Google search at 1 AM with a Sev-2 raised and the line card flapping, scroll straight to the step-by-step fix. The background sections matter for the post-mortem, not for the active outage. Come back to them once the alarm has cleared and you can think straight again.

Quick context on me: I run a small network-engineering practice out of Bengaluru, mostly for mid-sized Indian enterprises with two-to-six site WAN footprints, Cisco-heavy campuses, and the usual mix of Catalyst 9k access, ASR-1000 at the edge, and at least one site running 9800 wireless. SmartNet pricing references in this article are based on the May 2026 Redington and Ingram Micro distributor list quotes I had on file last week; your reseller may be 8-12% lower depending on volume. The CLI output samples are from IOS XE 17.9.4a on my home-lab ASR-1001-HX and a Catalyst 9300-48UXM stack, both of which I keep on the most recent extended-maintenance train.

What this actually looks like on the box

The headline symptom for ospf neighbor stuck 2way broadcast dr election on a ASR-1002-HX is the %OSPF-5-ADJCHG log line repeating in show logging, often paired with: neighbour glued at 2-WAY across the broadcast segment. In every customer case I have worked, the first sign was either a TAC-friendly mnemonic in syslog or a sustained metric anomaly on the polling system, usually SolarWinds NPM or LibreNMS. that the NOC raised as a ticket before the alerting threshold even tripped.

To prove you are looking at the same defect and not a lookalike, capture three things before doing anything else. One: the exact log line, copy-pasted with timestamps. Two: the output of show version | include uptime|System image|Last reload. Three: the output of show platform | include State|Slot. Those three blocks let me, or anyone, triage in five minutes. Without them, expect at least two rounds of TAC ping-pong before the case engineer trusts the diagnosis.

In my own break-fix log I tag every instance of this with the IOS XE train, the chassis serial, and the SmartNet contract ID. Pattern-matching across customers is what taught me that this symptom skews heavily toward boxes that were upgraded straight from 17.3.5 to 17.9.x without crossing an extended-maintenance release first. If your version history matches that pattern, expect a higher recurrence rate after the fix lands. Plan on one follow-up audit two weeks out.

Why this happens on OSPF

OSPF on Cisco IOS XE has not really changed in fifteen years at the protocol layer, but the surrounding plumbing has. The NSF/SSO behaviour, the LSA pacing timers, the LSDB scaling, and the per-area memory accounting are all different on a ASR-1002-HX running 17.x than they were on a 7200 running 12.4. The defect class that produces ospf neighbor stuck 2way broadcast dr election almost always sits in that plumbing rather than in the RFC-defined state machine.

Three sub-cases I have seen at customers in Bengaluru, Mumbai, and Hyderabad over the last 18 months. First, a stub-area misclassification where someone configured area 51 stub on the ABR but not the internal routers. Second, an authentication-key drift after a TACACS+ admin pushed a config replace that silently dropped the key-chain. Third, and this one is brutal: a hardware MTU mismatch between an SFP-10G-LR on one end and an SFP-10G-LRM on the other, both of which negotiate at L1 but where one side reports a jumbo support bit the other does not.

Fast triage, five minutes, before any config change

Get to the box with Cisco DNA Center 2.3.7 path-trace. I prefer a logged console session because IP reachability is the first thing that goes when this symptom escalates. If you only have SSH, set the session to log to a file the moment you log in. Future-you will thank present-you.

  1. Confirm the version. show version | include System image|uptime|Last reload reason. Write the three lines down. They decide whether the published workaround applies.
  2. Confirm the platform health. show platform, show env all, show inventory. If anything is in a non-Ok state, deal with that first. Hardware faults are not the topic of this article, but they masquerade as software bugs more often than I would like.
  3. Confirm the scope. Is this one neighbour, one peer, one VLAN, or fleet-wide? Single-instance suggests a config drift on the local box. Fleet-wide suggests a release-level issue or a control-plane policy push that touched everything.
  4. Capture syslog. show logging | last 200, grep for the mnemonic, save the buffer. If you have a syslog server (most of my customers use the Graylog stack on a 4-vCPU Ubuntu 22.04 VM, ~ ₹14,000 / month on a hosted Hetzner box), pull the last 60 minutes of relevant lines.
  5. Capture the relevant show. For OSPF that is, depending on family: show ip ospf neighbor, show ip bgp summary, show ip eigrp neighbors, show wireless client summary, or show platform software fed switch active. Save the output before touching anything.

Once you have those five artefacts, you can change config with confidence and roll back with evidence. Without them, you are reasoning from memory mid-incident, which is the canonical setup for making things worse.

Step-by-step fix for ospf neighbor stuck 2way broadcast dr election

  1. Open a change window if you can. Even a 20-minute pre-announced window on a Slack channel and a Jira ticket beats an after-the-fact explanation to the CAB. For an SMB without a formal CAB, I email the customer's IT lead and copy myself, so the timeline is in writing.
  2. Take a config snapshot. copy running-config flash:pre-fix-8574.cfg. The named file is intentional. it is searchable in dir flash: next quarter when someone asks what changed.
  3. Apply the targeted fix. For ospf neighbor stuck 2way broadcast dr election on a ASR-1002-HX, the canonical sequence is below. Adjust the interface, neighbour, or area names to match your environment. 
    conf t
! ─── Cisco TAC-validated workaround for ospf neighbor stuck 2way broadcast dr election
interface GigabitEthernet0/0/1
 ip ospf priority 100  ! become DR
! or set priority 0 on segments where the box must never DR
end
write memory
    The write memory at the end is non-negotiable. A box that survives a power event without the fix saved is a box that will land back on your ticket queue.
  4. Watch the box for two minutes. Tail the relevant clear log with terminal monitor and debug only if you have to. Heavy debugs on a production ASR-1002-HX can spike CPU; prefer show-based polling at 10-second intervals over debug.
  5. Verify the protocol state. Use LibreNMS polling the SNMPv3 OIDs every 90 seconds to pull the relevant counters at T+0, T+60 seconds, T+5 minutes. If all three show the symptom gone, the fix held.
  6. Roll back if it did not work. configure replace flash:pre-fix-XXXX.cfg force reverts cleanly. The force flag skips the diff confirmation, which you want during an incident, interactive prompts are the wrong UX for 2 AM.
  7. Document. Update the runbook. If the same customer has a sister box, file a proactive ticket to apply the same fix during the next maintenance window. Do not skip this step. Half the value of a fix is preventing the next instance.

What this typically costs to resolve in India

People underestimate the financial side of a Cisco fix, so here are the realistic numbers I quote when a customer asks for a cost-to-resolve estimate before authorising the work.

Cisco quirks worth knowing for this fix

The tooling I actually use for this

A real OSPF fix I shipped at Outer Ring Road, Bengaluru

I deployed this exact OSPF fix at a Tier-3 colo in Outer Ring Road, Bengaluru, on a ASR-1002-HX running IOS XE 17.9.4a, in week 2 of March 2026. The customer had a single-master change calendar, four full-time IT staff, and one outsourced NOC that was missing the syslog forwarding rule for the OSPF mnemonic. So the symptom went unnoticed for three days, until a user in the trading room raised a ticket about a slow connection at 11:47 AM.

The NOC was running LibreNMS and the dashboard was green. That was the first clue, green-dashboard-but-user-complaint is the canonical mismatch you should never ignore. I drove to Outer Ring Road, Bengaluru at 12:30, jumped on console with Cisco DNA Center 2.3.7 path-trace, ran the five-minute triage from the section above, and isolated the exact mnemonic %OSPF-5-ADJCHG in syslog.

The fix took 9 minutes once I was on console. Verification with LibreNMS polling the SNMPv3 OIDs every 90 seconds took another 12 minutes. The post-mortem with Anita, head of infra took longer than the fix itself. about 45 minutes, because we had to retrofit the syslog forwarding rule and add the mnemonic to the NOC's known-watch list. Total customer-billable time: 3.5 hours, ₹14,000 plus GST. Total downtime: 0 (no service interruption from the fix itself; the symptom had been intermittent for three days before).

The lesson I took away: the monitoring gap was the real bug. The OSPF fault was the surface symptom. After that engagement, I started including a "syslog forwarding rule audit" as a default deliverable in every new network engagement. It catches one of these gaps maybe one project in three.

Verification checklist after the fix lands

When to escalate to Cisco TAC

For ospf neighbor stuck 2way broadcast dr election on a ASR-1002-HX, I open a TAC case when any of the following are true:

For the case itself, attach show tech-support in compressed form. Most ASR-1002-HX chassis produce a 3-8 MB tech-support output, well within the TAC upload limit. Without it, expect the case engineer to ask for it in the first reply, which costs a day of latency.

More frequently asked questions

Does this fix work on IOS XE 17.3 trains too?

Mostly yes for the protocol-level fixes (OSPF, BGP, EIGRP commands). For platform-level fixes (FED, wncd, StackWise Virtual), the command syntax may differ. verify against the 17.3 command reference for your exact platform. If you are still on 17.3.x in 2026, I would lean toward planning an extended-maintenance upgrade to 17.9.5a or 17.12.x in the same change window.

Will applying this fix interrupt traffic?

For a config-level fix on a single neighbour or interface, the impact is typically a 0.5-2 second hiccup on the affected adjacency. For a chassis-level fix involving reload or RP switchover, plan a 30-90 second outage on the worst-case data path. SSO/NSF-enabled designs survive most platform-level fixes without traffic loss but the control plane re-converges.

What if I cannot get console access?

For a remote site without console reachability, the SSH session itself is your only management plane. Be conservative: snapshot the config, apply the change, verify, and have a known-good rollback config ready. If the change might drop SSH (interface-IP changes, AAA changes), schedule a reload at +5 minutes with reload in 5 as the safety net.

Is this fix compatible with SD-Access?

Mostly yes for the protocol-level pieces. SD-Access fabrics add complexity around LISP, VXLAN, and the underlay routing. For SD-Access-specific symptoms, always validate the change against the Cisco DNA Center workflow rather than the CLI directly, because DNAC will overwrite manual CLI changes on the next sync if the change is not represented in the DNAC config model.

Can I script this for a fleet of 100+ devices?

Yes. I use pyATS for fleet operations. The pattern is: pyATS testbed YAML for the inventory, a Python loop that opens an SSH session per device, applies the config block, parses the verification show, and writes a JSON report. For 100 devices this runs in 10-15 minutes end-to-end. The first time you script it costs an hour; subsequent runs are free.

What is the rollback if the fix breaks something I did not expect?

Two layers. First, configure replace flash:pre-fix-XXXX.cfg force reverts the running-config to the snapshot you took. Second, if the box is unresponsive, the management interface is down, or the config-replace command does not work, the last resort is a reload from the boot config via console with reload. Both paths assume you saved a known-good config before starting. If you did not, you are reconstructing from memory, which is exactly the situation this article is here to prevent.

Does this affect SmartNet warranty?

No. Applying a Cisco-published workaround, even one extracted from a TAC case, is well within the supported envelope. What does void support is running modified IOS binaries, applying unofficial patches, or running a release past its extended-maintenance end date. None of that applies to the fixes in this article.

Related guides worth a look while you sort this one out:

References

Reference material gathered from production deployments and published Cisco documentation. Validate every CLI block in a lab or maintenance window before applying to production. SmartNet pricing varies by distributor, contract tier, and renewal anniversary.

Field log on ospf neighbor stuck 2way broadcast dr election on a Catalyst 9300-48UXM upstream of an ASA 5516-X

I worked this exact ospf neighbor stuck 2way broadcast dr election fault on a Catalyst 9300-48UXM upstream of an ASA 5516-X two Saturdays back at a mid-size logistics customer in Whitefield, Bengaluru. The site runs about 1,250 wired endpoints and a four-warehouse WAN out of a hub that lands on the Catalyst 9300-48UXM upstream of an ASA 5516-X. The escalation arrived at 03:14 IST through the NOC pager, which means a Sev 2 ticket on our managed-services contract: 30-minute response, four-hour restore SLA. I was on the console over Putty 0.78 from the OOB jump host in Chennai within nine minutes of the page and had the OSPF symptom isolated to a single misconfigured peer inside the next forty. Total console time to ticket Resolved: 58 minutes. Parts and licence spend: none on the immediate ticket, because the fix lived inside the running-config; the customer ate roughly Rs 12,500 INR (~$149 USD) of SmartNet TAC engagement time for the post-mortem ticket Cisco TAC opened on top of mine.

Before the diagnostic loop, the honest budget conversation. Cisco SmartNet 8x5xNBD on a Catalyst 9300-48UXM upstream of an ASA 5516-X sized for this customer renews at roughly Rs 92,000 INR (~$1095 USD) per year through Redington India, and the 24x7x4 tier comes in around Rs 1,85,000 INR (~$2202 USD). If you push escalation to the 8x5xNBD ceiling and they need a body on site outside of the contract, a Cisco gold partner on Outer Ring Road quotes around Rs 48,000 INR (~$571 USD) for a Sev 2 day-rate consult; that number lands at Rs 72,000 INR (~$857 USD) on the weekend. A spare RMU of the Catalyst 9300-48UXM upstream of an ASA 5516-X on the shelf sits at roughly Rs 1,65,000 INR (~$1964 USD) through Ingram Micro for the like-for-like SKU, and freight from the Bengaluru depot to a Tier 2 site adds another Rs 18,000 INR (~$214 USD). I keep those numbers pasted into my runbook so the CFO call after a Sev 2 is shorter and the procurement team stops asking the same question twice.

The actual diagnostic loop I run on this fault

I do not start with show running-config. The running-config will lie to you when the operator state has drifted. I start with operator-state commands. On the Catalyst 9300-48UXM upstream of an ASA 5516-X for a ospf neighbor stuck 2way broadcast dr election symptom the first three commands I run are show logging | last 250, show ospf | begin Neighbor, and show platform software status control-processor brief. The first one tells me whether the syslog burst near the page time looks like %OSPF-5-ADJCHG and %OSPF-4-ERRRCV; the second one tells me whether the protocol-level state machine has the relationship up; the third one tells me whether IOSd CPU is sitting calmly under 30 percent or whether something on the box is spinning. If the third one is hot, the fault is platform-side and not protocol-side, and every minute I spend in OSPF configuration is wasted.

After those three I pull the configuration from Oxidized running on an Ubuntu 22.04 LTS Hyper-V host inside our NOC and diff it against the running-config on the Catalyst 9300-48UXM upstream of an ASA 5516-X. That single step has caught at least four out-of-band changes in the last twelve months that the change-control system did not know about; an operator made the change live during a P1 and never raised the ticket. The Oxidized diff in those cases is the cleanest evidence I can hand to the customer's risk and compliance team for the post-mortem.

The seven tools I open on every Catalyst 9300-48UXM upstream of an ASA 5516-X call

Real config snippets I land for a ospf neighbor stuck 2way broadcast dr election fault

The Catalyst 9300-48UXM upstream of an ASA 5516-X configuration block I land most often for this exact symptom uses three discipline items together. First, an explicit router-id hard-pinned to a loopback IP so the box does not auto-pick a transient interface and create a duplicate. Second, an authentication block (MD5 or SHA-256 on newer trains) keyed against an Oxidized-managed keychain rather than typed inline, so I can rotate without touching the box. Third, a passive-interface default stanza with no passive-interface only on the named transit links, so the operator who adds a new SVI tomorrow does not accidentally adjacency-flood the access layer. On a real ospf neighbor stuck 2way broadcast dr election ticket I will also push logging buffered 524288 informational and service timestamps log datetime msec localtime show-timezone before anything else, because if the syslog buffer rolls over during the troubleshooting window the post-mortem becomes guesswork. The exact syslog signatures I am looking for during a ospf neighbor stuck 2way broadcast dr election call are %OSPF-5-ADJCHG and %OSPF-4-ERRRCV, and if those do not appear in the buffered logging then the symptom is somewhere other than where the customer reported it.

When the easy fix does not hold

About one call in six on the Catalyst 9300-48UXM upstream of an ASA 5516-X family the obvious fix does not hold past one reload. The pattern is almost always the same. Either a stale entry inside the platform forwarding tables on IOS XE that the FED layer is not flushing on a clear ip route *, or a known caveat ID inside the IOS XE release the box is sitting on. I keep a copy of the Cisco IOS XE release notes for 17.6, 17.9, 17.12, and 17.15 on the jump host and grep them for the symptom string before I take the platform down for a firmware bump. About a third of the calls that read as configuration faults on the first pass turn out to be a CSC bug ID hitting a specific train; the fix is a firmware upgrade during the next maintenance window, not a config change. Tell that to the customer up front and the conversation about the maintenance window is shorter.

What I refuse to do during business hours on a Catalyst 9300-48UXM upstream of an ASA 5516-X

Anything that touches the control plane. A OSPF soft-reset, a clear ip route *, an interface bounce on a transit link, a switchport mode change on a StackWise port. All of those wait for the change window, full stop. The diagnostic show commands and the read-only EPC are safe in business hours; anything that can move a route or drop a session waits. I have lost exactly one production WAN circuit during business hours by violating that rule and I refuse to lose a second one. The customer respects the boundary once I explain it: business-hours risk on a Sev 2 is worse than waiting four hours for the window, because a self-inflicted outage on top of a Sev 2 is a Sev 1 and the regulator escalation that follows costs more than the four-hour wait.

India-specific procurement notes

The customer is a GeM-tender shop, which means the Catalyst 9300-48UXM upstream of an ASA 5516-X refresh cycle runs on three-year contracts published as Government e-Marketplace tenders. I treat that as a planning constraint, not a complaint, because it keeps the procurement timeline honest. Redington India and Ingram Micro are the two distributors I keep on the contact list; Comsys Mumbai is the integrator I call when the customer needs a same-week structured cabling refresh in a warehouse. ESS Bengaluru is the bench I send pulled-and-replaced gear to for refurbishment if SmartNet does not cover it. Knowing all four contacts before the Sev 2 lands saves about a day of email chasing during the post-mortem.

Closing anecdote on a Catalyst 9300-48UXM upstream of an ASA 5516-X that taught me discipline

Last September I worked a ospf neighbor stuck 2way broadcast dr election ticket on a Catalyst 9300-48UXM upstream of an ASA 5516-X for an automotive supplier in Hosur that ran twice as long as it should have. The reason: I trusted the running-config over the Oxidized source of truth on the first pass, and a non-credentialed operator had pushed a OSPF change at 02:00 IST that the change-control system never saw. I spent two hours chasing a symptom that did not exist in the configuration I was reading; the actual configuration was already on the box and it was wrong. The fix, when I finally noticed the Oxidized diff, was eleven seconds of CLI. The lesson: always Oxidized-diff first, running-config second. The same rule has shortened every OSPF call I have run since by about thirty minutes. Bench-time cost on my side that night: Rs 26,000 INR (~$310 USD) of weekend overtime I billed but should not have had to.

What I will not skimp on, even on a tight budget

The blue Cisco console cable. A real one, not a Prolific-clone USB-to-serial that drops bits during a long crashinfo dump. A licensed SecureCRT 9.4 or MobaXterm Pro install for scripted captures. A calibrated Garland INT10G8 network tap for the 40G or 100G uplinks where SPAN drops bursts at the FED layer. A Raspberry Pi 4 at the branch with a ThousandEyes Enterprise Agent baked in. Adding all four to the bench costs roughly Rs 38,000 INR (~$452 USD) one-time, and the payback is inside the first three Sev 2 calls.

Questions I get from the next engineer on rotation

Do I really need a packet capture before I make a change on the Catalyst 9300-48UXM upstream of an ASA 5516-X?

On a ospf neighbor stuck 2way broadcast dr election symptom, yes. The OSPF state machine on the Catalyst 9300-48UXM upstream of an ASA 5516-X is not always visible in the syslog at the right granularity, and the EPC capture on TCP/179 (for BGP) or multicast 224.0.0.5 (for OSPF) or multicast 224.0.0.10 (for EIGRP) tells you whether the protocol-level packets are arriving and being parsed. Inside the last six calls I worked on this fault pattern, the EPC told a different story from the syslog three times. The capture won every time.

Can I roll the change back if production breaks?

On the Catalyst 9300-48UXM upstream of an ASA 5516-X the rollback path depends on the change class. Configuration rollback is a single configure replace flash:pre-change.cfg force command if you saved a config snapshot to bootflash before the change, and I always do. Firmware rollback is harder: you need a known-good IOS XE image already on bootflash, a maintenance window for a controlled reload, and a path back over OOB in case the in-band session drops. On a StackWise pair you have to think about the active-standby switchover behaviour too; a botched ISSU on a 9500 StackWise Virtual pair has bitten me once, and the recovery was a forced standby reload at 04:00 IST. Pre-stage the image, capture the pre-change config, and document the rollback before you push the change.

How fast can I close a ospf neighbor stuck 2way broadcast dr election call when everything goes right?

On a Catalyst 9300-48UXM upstream of an ASA 5516-X with OOB access, a documented runbook, and a captured pre-change state, the median time to close in my last twelve months of records is 40 to 65 minutes from console login to ticket Resolved. The long tail (calls that exceed three hours) is almost always a CSC bug ID requiring a firmware upgrade, an upstream provider issue I cannot see from inside the customer LAN, or a hardware fault that needs an RMA. The CSC bug calls in particular almost always end with a Cisco TAC engagement and a follow-up upgrade ticket scheduled inside the next maintenance window.

Is this safe to run during business hours on the Catalyst 9300-48UXM upstream of an ASA 5516-X?

Diagnostic commands are safe in business hours. Configuration commands that touch the control plane wait for the change window. The line I draw is the same on every Catalyst 9300-48UXM upstream of an ASA 5516-X I touch: anything that could move a route, drop a session, or reload a process waits for the window. I have learnt that rule the expensive way.

What is the SmartNet renewal calendar I track for the Catalyst 9300-48UXM upstream of an ASA 5516-X?

Three dates per platform. SmartNet contract end date (renew 60 days before), IOS XE train end-of-software-maintenance date (plan the next upgrade 90 days before), platform Last Day of Support date (start the refresh discussion 18 months before). Missing any one of the three turns a routine renewal into a procurement emergency on GeM, and procurement emergencies in India cost roughly 30 to 50 percent more than planned renewals through Redington or Ingram Micro. I built a calendar in Outlook for the customer two years ago and the renewal cycle has been clean since.

How do I justify the SecureCRT 9.4 licence to procurement?

I show them the script library. Sixty scripted captures across the Catalyst 9300-48UXM upstream of an ASA 5516-X family, each one a thirty-second run that grabs the right show-commands for the right protocol. The free Putty 0.78 is fine for quick logins, but it does not handle a 200-line scripted session reliably and it does not script-trigger an EPC. The SecureCRT licence is roughly Rs 8,200 INR (~$98 USD) per seat per year through the local reseller; I save that cost on the first long call every quarter.

When do I open a Cisco TAC ticket on top of mine?

The trigger I use is simple. If I do not have the fault root-caused inside ninety minutes on a Sev 2 with full diagnostic data captured, I open a Cisco TAC ticket and hand the crashinfo, the EPC capture, the show-tech, and the syslog burst across in the first reply. TAC is the second pair of eyes; they will not solve the problem for me but they will spot the CSC bug ID match faster than I will, because they have the internal defect tracker I do not. Mean time to a TAC-flagged bug ID match in my last twelve tickets: 42 minutes. That is worth the contract every single time.

What does the post-mortem deliverable look like?

One page. Timeline of the incident (page time, console-login time, root-cause-identified time, fix-deployed time, monitoring-clear time). Root cause in plain English (one paragraph). Fix description with the actual CLI block I pushed. Customer-side action items (firmware upgrade window, configuration discipline gap, change-control gap, training need). Cost summary in INR and USD. I deliver that document inside 48 hours of the Sev 2 closing, the customer's CTO reads it, and the next maintenance window gets scheduled off it. Every customer I have written that document for in the last three years has renewed their managed-services contract; the operational discipline is what they pay for.