[PATCH cluster/docs/manager/widget-toolkit v4 0/8] add warning messages for high token timeouts in clusters

[PATCH cluster/docs/manager/widget-toolkit v4 0/8] add warning messages for high token timeouts in clusters

[Michael Köppl]

This patch series introduces warnings informing users about high token
timeouts in their clusters. A recent change [0] lowered the token
coefficient for clusters and allowed adapting it. However, this change
only affects new clusters. As described in [1], users with existing
cluster should be informed about the high token timeouts in their
configurations and what they can do to alleviate this problem.

Thus, warnings are added to the `pvecm status` command as well as to the
cluster join info dialog in the web UI. The warning in the web UI warns
users about the effect adding another node would have to allow them to
make an informed change before adding another node.

changes since v3 (thanks to @Fabian, @Friedrich for the feedback):
- Rebase on latest master for all affected repos
- Adapt the scan_extjs_file function to allow detecting `get_help_link`
  function calls across multiple lines
- Move up the paragraph in the documentation to better fit in the
  updated section
- Use the output of `corosync-cmapctl` to the token and consensus
  timeouts instead of re-implementing the calculation. This also means
  that, at least for now, the calculation can only be done for the
  current number of nodes, to avoid making the calculation more complex
  than it needs to be. This is based on feedback [2] on v3.
- Instead of implementing the calculation of warning levels and messages
  twice (in pve-cluster and pve-manager separately), add a warnings
  property to the join info endpoint that consists of an array of
  objects with a type, level, and message field. The warning level and
  message are then constructed in pve-cluster, returned by the join info
  endpoint and only displayed by pve-manager. The ClusterEdit dialog can
  now display arbitrary warnings with their levels. The type field was
  added to be able to link to specific parts of the documentation for
  specific errors. This is based on feedback [2] from v4.
- Add a patch to proxmox-widget-toolkit that adds a .pmx-critical CSS
  class that is similar to .pmx-hint, but for more critical errors. This
  was done based on the off-list suggestion by @Fabian that different
  warnings levels might warrant different colors in this case.

Also, thanks to @Lukas for testing v3!

changes since v2 (thanks to @Lukas and @Friedrich for the feedback):
- use "lowering" instead of "changing" for the warning strings
- replace leftover hard-coded PVE docs link with `man pvecm`
- update descriptions of timeout_warning_level and expected_timeout
  params such that they say "membership recovery timeout", to more
  clearly state which timeout this is about
- update function names for get_timeout_warning_level and
  get_timeout_warning to
  calculate_membership_recovery_timeout_warning_level and
  calculate_membership_recovery_timeout_warning respectively

changes since v1 (thanks to @Friedrich for the feedback on v1):
- add pve-docs patch to allow using get_help_link to directly link to
  an anchor in the local documentation (then used to link to the section
  on changing the token coefficient)
- add pve-docs patch to define explicit anchor for the "Changing the
  Token Coefficient" section
- add pve-docs patch extending the section for Changing the Token
  Coefficient slightly, informing users of the potential warning
  messages in the pvecm status output
- change the threshold for "strongly recommend" from 50s to 45s as
  suggested by @Friedrich
- adapted the name of calculate_total_timeout to
  calculate_membership_recovery_timeout
- adapted commit messages for preparatory pve-manager patch (no
  functional changes intended)
- moved the warning message in pvecm from `pvecm nodes` to `pvecm status`
- replaced the URL in the pvecm warning message with a reference to the
  pvecm man pages
- link to local documentation in ClusterEdit.js

[0] https://git.proxmox.com/?p=pve-cluster.git;a=commit;h=a7b1c765b9223a81fb2dc4f072d6a6c095583cda
[1] https://bugzilla.proxmox.com/show_bug.cgi?id=7398
[2] https://lore.proxmox.com/pve-devel/1779112787.r3e8af5igi.astroid@yuna.none/

pve-docs:

Michael Köppl (2):
  asciidoc-pve: allow linking sections with get_help_link
  pvecm: add info about warnings regarding token coefficient

 pvecm.adoc              |  5 +++++
 scripts/asciidoc-pve.in | 19 ++++++++++---------
 2 files changed, 15 insertions(+), 9 deletions(-)


pve-cluster:

Michael Köppl (3):
  add functions to determine warning level for high token timeouts
  pvecm: warn users of high token timeouts when using status command
  api: join info: add totem timeout warning message and level

 src/PVE/API2/ClusterConfig.pm | 21 +++++++++++++
 src/PVE/CLI/pvecm.pm          |  7 +++++
 src/PVE/Corosync.pm           | 59 +++++++++++++++++++++++++++++++++++
 3 files changed, 87 insertions(+)


proxmox-widget-toolkit:

Michael Köppl (1):
  add pmx-critical CSS class

 src/css/ext6-pmx.css                        |  4 ++++
 src/proxmox-dark/scss/proxmox/_general.scss | 15 +++++++++++----
 2 files changed, 15 insertions(+), 4 deletions(-)


pve-manager:

Michael Köppl (2):
  ui: cluster info: move initialization of items to initComponent
  ui: cluster info: display warnings from the join info endpoint

 www/manager6/dc/Cluster.js     |   3 +
 www/manager6/dc/ClusterEdit.js | 140 ++++++++++++++++++++++-----------
 2 files changed, 95 insertions(+), 48 deletions(-)


Summary over all repositories:
  9 files changed, 212 insertions(+), 61 deletions(-)

-- 
Generated by murpp 0.11.0

[PATCH docs v4 1/8] asciidoc-pve: allow linking sections with get_help_link

[Michael Köppl]

scan_extjs_file previously only scanned for occurrences of onlineHelp.
Linking to specific sections of the documentation with get_help_link was
not possible without an accompanying onlineHelp entry. Extend the regex
to also match get_help_link('blockid') calls.

biome may reformat function calls across multiple lines, so a scan which
reads one line at a time would miss those occurrences. Switch from
reading the file line by line to reading the whole file and matching
globally. In addition, tolerate an optional trailing comma after the
blockid argument. Line numbers for die/warn messages are reconstructed
from the match offset since $. is no longer meaningful when matching
against the full buffer.

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
Feedback very much welcome. I ran into this problem when biome started
formatting the get_help_link function calls to multiple lines.
Alternatively, I could've added a `biome-ignore format: ...` to the
affected lines in pve-manager, but since it looks like we're not
ignoring the rules anywhere, I chose to adapt the scan function. I
tested this on both onlineHelp links and get_help_link links.

 scripts/asciidoc-pve.in | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/scripts/asciidoc-pve.in b/scripts/asciidoc-pve.in
index d42ddbe9..12fde424 100644
--- a/scripts/asciidoc-pve.in
+++ b/scripts/asciidoc-pve.in
@@ -463,16 +463,17 @@ sub scan_extjs_file {
 
     debug("scan-extjs $filename");
 
-    while (defined(my $line = <$fh>)) {
-        if ($line =~ m/\s+onlineHelp:\s*[\'\"]([^{}\[\]\'\"]+)[\'\"]/) {
-            my $blockid = $1;
-            my $link = $fileinfo->{blockid_target}->{default}->{$blockid};
-            if (!(defined($link) || defined($online_help_links->{$blockid}))) {
-                die "undefined blockid '$blockid' ($filename, line $.)\n" if !$allow_missing;
-                warn "ignoring undefined blockid '$blockid' ($filename, line $.)\n";
-            }
-            $res_data->{$blockid} = 1;
+    my $content = do { local $/; <$fh> };
+
+    while ($content =~ m/(?|\s+onlineHelp:\s*[\'\"]([^{}\[\]\'\"]+)[\'\"]|\bget_help_link\(\s*[\'\"]([^{}\[\]\'\"]+)[\'\"]\s*,?\s*\))/g) {
+        my $blockid = $1;
+        my $line_no = 1 + (substr($content, 0, $-[0]) =~ tr/\n//);
+        my $link = $fileinfo->{blockid_target}->{default}->{$blockid};
+        if (!(defined($link) || defined($online_help_links->{$blockid}))) {
+            die "undefined blockid '$blockid' ($filename, line $line_no)\n" if !$allow_missing;
+            warn "ignoring undefined blockid '$blockid' ($filename, line $line_no)\n";
         }
+        $res_data->{$blockid} = 1;
     }
 }
 
-- 
2.47.3

[PATCH docs v4 2/8] pvecm: add info about warnings regarding token coefficient

[Michael Köppl]

`pvecm status` might warn users of a high sum of token and consensus
timeout, recommending lowering the token coefficient. To make users
aware that these warnings may occur and to allow users to search for
this warning in the docs and man pages, extend the section on lowering
the token coefficient.

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
 pvecm.adoc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/pvecm.adoc b/pvecm.adoc
index 6469a0c0..d50a2c3a 100644
--- a/pvecm.adoc
+++ b/pvecm.adoc
@@ -1429,6 +1429,11 @@ so that transient timing variations do not push the cluster past the watchdog
 threshold. The recommended mechanism for lowering the token and consensus
 timeouts is lowering the token coefficient as explained below.
 
+Cluster commands may display a warning if the sum of the Corosync token and
+consensus timeouts is considered too high (e.g., "Changing the token coefficient
+is recommended"). To resolve this warning, it is recommended to lower the token
+coefficient.
+
 You can check the current token and consensus timeouts (in milliseconds) with
 the following command:
 
-- 
2.47.3

[PATCH cluster v4 3/8] add functions to determine warning level for high token timeouts

[Michael Köppl]

High token timeouts can lead to stability problems in clusters. To
inform users about the timeout in their current setup and give
recommendations regarding the token coefficient setting, introduce
functions to calculate the timeout as well as determine the warning
level.

Current token and consensus timeout are parsed from corosync-cmapctl's
output directly to avoid future drift between this implementation and
Corosync's implementation. The values are parsed from the output
assuming the following format:

    runtime.config.totem.consensus (u32) = 3750
    runtime.config.totem.token (u32) = 3125

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
 src/PVE/Corosync.pm | 59 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/src/PVE/Corosync.pm b/src/PVE/Corosync.pm
index aef0d31..d379710 100644
--- a/src/PVE/Corosync.pm
+++ b/src/PVE/Corosync.pm
@@ -534,4 +534,63 @@ sub resolve_hostname_like_corosync {
     return $match_ip_and_version->($resolved_ip);
 }
 
+sub read_cmap {
+    my $cmap = {};
+    my $rc = eval {
+        PVE::Tools::run_command(
+            ['corosync-cmapctl'],
+            outfunc => sub {
+                my $line = shift;
+                if ($line =~ /^(\S+)\s+\(\w+\)\s+=\s+(.*)$/) {
+                    $cmap->{$1} = $2;
+                }
+            },
+        );
+        1;
+    };
+    return undef if !$rc;
+    return $cmap;
+}
+
+sub calculate_membership_recovery_timeout {
+    my $cmap = read_cmap();
+    return undef if !$cmap;
+
+    my $token = $cmap->{'runtime.config.totem.token'};
+    my $consensus = $cmap->{'runtime.config.totem.consensus'};
+    return undef if !defined($token) || !defined($consensus);
+
+    return ($token + $consensus) / 1000.0;
+}
+
+sub get_membership_recovery_timeout_warning_level {
+    my ($total_timeout_secs) = @_;
+
+    if ($total_timeout_secs > 45) {
+        return 'critical';
+    } elsif ($total_timeout_secs > 40) {
+        return 'warning';
+    } elsif ($total_timeout_secs > 30) {
+        return 'info';
+    }
+
+    return undef;
+}
+
+sub get_membership_recovery_timeout_warning {
+    my ($total_timeout_secs) = @_;
+
+    my $level = get_membership_recovery_timeout_warning_level($total_timeout_secs);
+    return if !defined($level);
+
+    my $level_msg = {
+        critical => "Lowering the token coefficient is strongly recommended",
+        warning => "Lowering the token coefficient is recommended",
+        info => "The token coefficient can be optimized",
+    }->{$level};
+
+    my $msg = "Sum of Corosync token and consensus timeout is ${total_timeout_secs}s. $level_msg.";
+    return ($level, $msg);
+}
+
 1;
-- 
2.47.3

[PATCH cluster v4 4/8] pvecm: warn users of high token timeouts when using status command

[Michael Köppl]

If the calculated token timeout is above certain thresholds, display a
warning for users when running `pvecm status` as part of the Cluster
Information block. Also points users to the documentation regarding
potential adaptations to their cluster configuration to alleviate the
problem.

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
 src/PVE/CLI/pvecm.pm | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/PVE/CLI/pvecm.pm b/src/PVE/CLI/pvecm.pm
index 7d393a8..192adb7 100755
--- a/src/PVE/CLI/pvecm.pm
+++ b/src/PVE/CLI/pvecm.pm
@@ -561,6 +561,13 @@ __PACKAGE__->register_method({
             $print_info->('Transport', 'transport', 'knet');
             $print_info->('Secure auth', 'secauth', 'off');
             printf "\n";
+
+            my $total_timeout_secs = PVE::Corosync::calculate_membership_recovery_timeout();
+            my ($level, $msg) =
+                PVE::Corosync::get_membership_recovery_timeout_warning($total_timeout_secs);
+            if (defined($msg)) {
+                warn "$msg See 'man pvecm' for details.\n\n";
+            }
         }
 
         exec('corosync-quorumtool', '-siH');
-- 
2.47.3

[PATCH cluster v4 5/8] api: join info: add totem timeout warning message and level

[Michael Köppl]

The warning message and level based on the calculated membership
recovery timeout provide additional information to users on whether
the token coefficient used in their Corosync cluster could be
optimized, or if a change is (strongly) recommended. This lets users
make an informed decision about potentially reducing the coefficient
before adding another node to their cluster.

The `warnings` property is defined as an object with `message`, `level`,
and `type` fields to be expandable for additional errors or warnings in
the future and also allow for easily distinguishing between different
kinds of warnings and their levels.

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
 src/PVE/API2/ClusterConfig.pm | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/src/PVE/API2/ClusterConfig.pm b/src/PVE/API2/ClusterConfig.pm
index bbed40e..2172ab1 100644
--- a/src/PVE/API2/ClusterConfig.pm
+++ b/src/PVE/API2/ClusterConfig.pm
@@ -535,6 +535,7 @@ __PACKAGE__->register_method({
         check => ['perm', '/', ['Sys.Audit']],
     },
     method => 'GET',
+    protected => 1,
     description => "Get information needed to join this cluster over the connected node.",
     parameters => {
         additionalProperties => 0,
@@ -571,6 +572,19 @@ __PACKAGE__->register_method({
             preferred_node => get_standard_option('pve-node'),
             totem => { type => 'object' },
             config_digest => { type => 'string' },
+            warnings => {
+                type => 'array',
+                optional => 1,
+                items => {
+                    type => 'object',
+                    additionalProperties => 1,
+                    properties => {
+                        type => { type => 'string' },
+                        level => { type => 'string' },
+                        message => { type => 'string' },
+                    },
+                },
+            },
         },
     },
     code => sub {
@@ -599,12 +613,19 @@ __PACKAGE__->register_method({
             $node->{pve_addr} = scalar(PVE::Cluster::remote_node_ip($name));
         }
 
+        my $total_timeout_secs = PVE::Corosync::calculate_membership_recovery_timeout();
+        my ($level, $msg) =
+            PVE::Corosync::get_membership_recovery_timeout_warning($total_timeout_secs);
+
         my $res = {
             nodelist => [values %$nodelist],
             preferred_node => $nodename,
             totem => $totem_cfg,
             config_digest => $corosync_config_digest,
         };
+        $res->{warnings} =
+            [{ type => 'corosync-membership-recovery-timeout', level => $level, message => $msg }]
+            if defined($msg);
 
         return $res;
     },
-- 
2.47.3

[PATCH widget-toolkit v4 6/8] add pmx-critical CSS class

[Michael Köppl]

This class simply defines the background color similar to pmx-hint, but
for more critical messages. The color used is the same as for invalid
rows, but use a separate class to ensure that background colors for
invalid rows and critical error messages can be changed independently.

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
Added this because I wanted to avoid using the proxmox-invalid-row class
for something that is pretty much a pmx-hint with a different color.

 src/css/ext6-pmx.css                        |  4 ++++
 src/proxmox-dark/scss/proxmox/_general.scss | 15 +++++++++++----
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/src/css/ext6-pmx.css b/src/css/ext6-pmx.css
index d8d9b8d..a33e83f 100644
--- a/src/css/ext6-pmx.css
+++ b/src/css/ext6-pmx.css
@@ -6,6 +6,10 @@
     background-color: LightYellow;
 }
 
+.pmx-critical {
+    background-color: #f3d6d7;
+}
+
 .proxmox-tags-full .proxmox-tag-light,
 .proxmox-tags-full .proxmox-tag-dark {
     border-radius: 3px;
diff --git a/src/proxmox-dark/scss/proxmox/_general.scss b/src/proxmox-dark/scss/proxmox/_general.scss
index dcbf049..9eba060 100644
--- a/src/proxmox-dark/scss/proxmox/_general.scss
+++ b/src/proxmox-dark/scss/proxmox/_general.scss
@@ -39,12 +39,19 @@ div.eol-notice + div[id^="panel-"] > div[id^="panel-"][id$="-bodyWrap"] > div {
   background-color: $background-warning;
 }
 
-.pmx-hint a {
-  color: $highlighted-text-alt;
+.pmx-critical {
+  background-color: $background-invalid;
 }
 
-.pmx-hint a:active {
-  color: $highlighted-text;
+.pmx-hint,
+.pmx-critical {
+  a {
+    color: $highlighted-text-alt;
+
+    &:active {
+      color: $highlighted-text;
+    }
+  }
 }
 
 // Unclickable elements (mostly for elements with conditional handlers)
-- 
2.47.3

[PATCH manager v4 7/8] ui: cluster info: move initialization of items to initComponent

[Michael Köppl]

This allows conditionally adding items to the form. No functional
changes intended.

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
 www/manager6/dc/ClusterEdit.js | 102 +++++++++++++++++----------------
 1 file changed, 54 insertions(+), 48 deletions(-)

diff --git a/www/manager6/dc/ClusterEdit.js b/www/manager6/dc/ClusterEdit.js
index 109325855..aff1515ab 100644
--- a/www/manager6/dc/ClusterEdit.js
+++ b/www/manager6/dc/ClusterEdit.js
@@ -57,58 +57,64 @@ Ext.define('PVE.ClusterInfoWindow', {
         totem: {},
     },
 
-    items: [
-        {
-            xtype: 'component',
-            border: false,
-            padding: '10 10 10 10',
-            html: gettext('Copy the Join Information here and use it on the node you want to add.'),
-        },
-        {
-            xtype: 'container',
-            layout: 'form',
-            border: false,
-            padding: '0 10 10 10',
-            items: [
-                {
-                    xtype: 'textfield',
-                    fieldLabel: gettext('IP Address'),
-                    cbind: {
-                        value: '{joinInfo.ipAddress}',
-                    },
-                    editable: false,
-                },
-                {
-                    xtype: 'textfield',
-                    fieldLabel: gettext('Fingerprint'),
-                    cbind: {
-                        value: '{joinInfo.fingerprint}',
+    initComponent: function () {
+        var me = this;
+
+        var joinInfo = me.joinInfo;
+
+        me.items = [];
+
+        me.items.push(
+            {
+                xtype: 'component',
+                border: false,
+                padding: '10 10 10 10',
+                html: gettext(
+                    'Copy the Join Information here and use it on the node you want to add.',
+                ),
+            },
+            {
+                xtype: 'container',
+                layout: 'form',
+                border: false,
+                padding: '0 10 10 10',
+                items: [
+                    {
+                        xtype: 'textfield',
+                        fieldLabel: gettext('IP Address'),
+                        value: joinInfo.ipAddress,
+                        editable: false,
                     },
-                    editable: false,
-                },
-                {
-                    xtype: 'textarea',
-                    inputId: 'pveSerializedClusterInfo',
-                    fieldLabel: gettext('Join Information'),
-                    grow: true,
-                    cbind: {
-                        joinInfo: '{joinInfo}',
+                    {
+                        xtype: 'textfield',
+                        fieldLabel: gettext('Fingerprint'),
+                        value: joinInfo.fingerprint,
+                        editable: false,
                     },
-                    editable: false,
-                    listeners: {
-                        afterrender: function (field) {
-                            if (!field.joinInfo) {
-                                return;
-                            }
-                            var jsons = Ext.JSON.encode(field.joinInfo);
-                            var base64s = Ext.util.Base64.encode(jsons);
-                            field.setValue(base64s);
+                    {
+                        xtype: 'textarea',
+                        inputId: 'pveSerializedClusterInfo',
+                        fieldLabel: gettext('Join Information'),
+                        grow: true,
+                        joinInfo: joinInfo,
+                        editable: false,
+                        listeners: {
+                            afterrender: function (field) {
+                                if (!field.joinInfo) {
+                                    return;
+                                }
+                                var jsons = Ext.JSON.encode(field.joinInfo);
+                                var base64s = Ext.util.Base64.encode(jsons);
+                                field.setValue(base64s);
+                            },
                         },
                     },
-                },
-            ],
-        },
-    ],
+                ],
+            },
+        );
+
+        me.callParent();
+    },
     dockedItems: [
         {
             dock: 'bottom',
-- 
2.47.3

[PATCH manager v4 8/8] ui: cluster info: display warnings from the join info endpoint

[Michael Köppl]

The join info endpoint may return a list of warnings, each with a
message, a warning level, and a warning type. Display these warnings,
with critical warnings being displayed in red, regular warnings in
yellow (as is the case for other warnings throughout the UI), and
informational messages without a background color. In addition, add a
mapping from certain warning types to anchors in the documentation, to
point users in the right direction.

Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
---
This is mostly based on off-list feedback that different levels of
warnings might warrant different colors. Because a "could be optimize"
in a color that usually warns users might be a bit much. At the same
time, a strong recommendation for lowering the token coefficient means
the timeout is really high and should *really* be lowered. I'm still not
entirely sure regarding the background for the informational message. I
thought about adding a `pmx-info` class or something similar that has a
similar color scheme to the .x-column-header-sort-ASC and
.x-column-header-sort-DESC classes.

 www/manager6/dc/Cluster.js     |  3 +++
 www/manager6/dc/ClusterEdit.js | 38 ++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/www/manager6/dc/Cluster.js b/www/manager6/dc/Cluster.js
index 2ec5588c3..1d654a9ec 100644
--- a/www/manager6/dc/Cluster.js
+++ b/www/manager6/dc/Cluster.js
@@ -86,11 +86,13 @@ Ext.define('PVE.ClusterAdministration', {
                             addr: '',
                             fp: '',
                         });
+                        vm.set('warnings', []);
                         return;
                     }
                     vm.set('totem', data.totem);
                     vm.set('isInCluster', !!data.totem.cluster_name);
                     vm.set('nodelist', data.nodelist);
+                    vm.set('warnings', data.warnings);
 
                     let nodeinfo = data.nodelist.find((el) => el.name === data.preferred_node);
 
@@ -133,6 +135,7 @@ Ext.define('PVE.ClusterAdministration', {
                             peerLinks: vm.get('preferred_node.peerLinks'),
                             ring_addr: vm.get('preferred_node.ring_addr'),
                             totem: vm.get('totem'),
+                            warnings: vm.get('warnings'),
                         },
                     });
                 },
diff --git a/www/manager6/dc/ClusterEdit.js b/www/manager6/dc/ClusterEdit.js
index aff1515ab..51dfe7137 100644
--- a/www/manager6/dc/ClusterEdit.js
+++ b/www/manager6/dc/ClusterEdit.js
@@ -55,6 +55,7 @@ Ext.define('PVE.ClusterInfoWindow', {
         ipAddress: undefined,
         fingerprint: undefined,
         totem: {},
+        warnings: undefined,
     },
 
     initComponent: function () {
@@ -113,6 +114,43 @@ Ext.define('PVE.ClusterInfoWindow', {
             },
         );
 
+        // Encode anchor links for certain warning types
+        const WARNING_HELP_LINKS = {
+            'corosync-membership-recovery-timeout': Proxmox.Utils.get_help_link(
+                'pvecm_changing_token_coefficient',
+            ),
+        };
+
+        for (const w of joinInfo.warnings ?? []) {
+            const helpAnchor = WARNING_HELP_LINKS[w.type];
+            let html = Ext.String.htmlEncode(w.message);
+            if (helpAnchor) {
+                const link = `<a target="_blank" href="${helpAnchor}">${gettext('the documentation')}</a>`;
+                html += ' ' + Ext.String.format(gettext('See {0} for details.'), link);
+            }
+
+            let cls;
+
+            switch (w.level) {
+                case 'info':
+                    cls = null;
+                    break;
+                case 'warning':
+                    cls = 'pmx-hint';
+                    break;
+                case 'critical':
+                    cls = 'pmx-critical';
+                    break;
+            }
+
+            me.items.push({
+                xtype: 'container',
+                border: false,
+                padding: '0 10 10 10',
+                items: [{ xtype: 'displayfield', userCls: cls, value: html }],
+            });
+        }
+
         me.callParent();
     },
     dockedItems: [
-- 
2.47.3