Avamar: Client Browse Times Out When Port 28002 Blocked or DNS Name Unresolved

Client browse operation times out.

The following symptoms may be observed when initiating a browse from the Avamar user interface:

• A timeout error appears while trying to browse a client for backup, restore, redirected restore, or dataset setup.
• The message indicates that the client did not respond within the allotted time.
• Specific error text similar to the example below displays:

The client was unable to complete this browse request within the allotted limit of 10 seconds. This can be caused by a directory structure with an unusually large number of sub-elements or an unusually low available CPU capacity at the client. Your options are to increase the time limit and Retry, or partial results.

Underlying Factors Leading to Client Browse Timeout

Network Connectivity Issues

• The Avamar client requires TCP port 28002 to be reachable from the utility node.
• If this port is blocked by a firewall or not listening on the client, the browse request cannot be completed.

Client Name Resolution Failures

• The client’s hostname must resolve to an IP address using Domain Name System (DNS) or the /etc/hosts file on the utility node.
• When the hostname is missing from DNS or the hosts file, the utility node cannot establish a connection, resulting in a timeout.

Resource Constraints on the Client

• Large directory structures with many subelements can exceed the default 10‑second browse window.
• Insufficient CPU capacity on the client can delay processing of the browse request, also causing the timeout.

Troubleshooting Avamar client browse timeout

1. Verify that the client port is reachable.

• From the Avamar Utility Node, attempt a Telnet connection to the client on port 28002.
• • Replace [CLIENT] with the client hostname or IP address:

telnet [CLIENT] 28002

• If the connection succeeds, the port is open and reachable.
• If the connection fails, go to step 2.

2. Open the required firewall port.

• On the client (or any intermediate firewall), ensure that TCP port 28002 is allowed.
• Typical commands (adjust for your firewall product):
• avfirewall is a hardened firewall. Script edit-firewall-rules.sh comes with Avamar server.

          It must be used to make any changes, or changes are lost during upgrades.
         

/usr/local/avamar/lib/admin/security/edit-firewall-rules.sh

The GoAV admin tool can also be used to make changes. Information can be found on the Dell support site, including instructions on how to download it: Avamar: GoAV Product Tool for Management and Troubleshooting

3. Confirm that the client name resolves correctly.

• Check DNS resolution for the client hostname:

nslookup [CLIENT]

• If the name does not resolve, the client name is missing from DNS or the /etc/hosts file.
• Update the DNS server (or /etc/hosts) to include an A record for the client.

4. Verify DNS changes.

• After updating DNS, clear any cached entries and re‑run the lookup.
  • Flush DNS cache on Linux (example):

    systemd-resolve --flush-caches

  • Re‑run the lookup:

    nslookup [CLIENT]

5. Retry the browse operation.

• Return to the Avamar user interface and attempt the client browse again.
• If the operation completes without a timeout, the issue is resolved.

Verification

• Successful Telnet to port 28002
• Client hostname resolves to the correct IP address
• Avamar user interface displays the client’s directory tree without a timeout message