I’m routing on the edge…

Leave a reply

In my last post (Routed Port vs. Switch Virtual Interface (SVI)), I have mentioned a consequence of using routed ports to interconnect access and core switches:

You have to route the traffic on the access switches.

Routing on the network access, the edge of the network, is not a question of performance. It is more of a management issue. Depending on the size of your network, and the number of subnets, you have to deal with lots of routes. And think about the effort, if you add, change or remove subnets from your network. This is not what you want to do with static routes. You need a routing protocol.

I’m routing on the edge…

5 (100%) 5 votes

Routed Port vs. Switch Virtual Interface (SVI)

1 Reply

Many years ago, networks consisted of repeaters, bridges and router. Switches are the successors of the bridges. A switch is nothing else than a multiport bridge, and a traditional switch doesn’t know how to pass traffic to a different broadcast domains (VLANs). Passing traffic between different broadcast domains, is a job for a router. A router has an IP interface in each broadcast domain, and the IP interface is used by the clients in the broadcast domain as a gateway.

Switch Virtual Interface

Routed Port vs. Switch Virtual Interface (SVI)

5 (100%) 5 votes

HPE 3PAR OS updates that fix VMware VAAI ATS Heartbeat issue

Leave a reply

Customers that use HPE 3PAR StoreServs with 3PAR OS 3.2.1 or 3.2.2 and VMware ESXi 5.5 U2 or later, might notice one or more of the following symptoms:

hosts lose connectivity to a VMFS5 datastore
hosts disconnect from the vCenter
VMs hang during I/O operations
you see the messages like these in the vobd.log or vCenter Events tab

Lost access to volume <uuid><volume name> due to connectivity issues. Recovery attempt is in progress and the outcome will be reported shortly

1	Lost access to volume <uuid><volume name> due to connectivity issues. Recovery attempt is in progress and the outcome will be reported shortly

you see the following messages in the vmkernel.log

ATS Miscompare detected beween test and set HB images at offset XXX on vol YYY

2015-11-20T22:12:47.194Z cpu13:33467)ScsiDeviceIO: 2645: Cmd(0x439dd0d7c400) 0x89, CmdSN 0x2f3dd6 from world 3937473 to dev &#34;naa.50002ac0049412fa&#34; failed H:0x0 D:0x2 P:0x0 Valid sense data: 0xe 0x1d 0x0.

ATS Miscompare detected beween test and set HB images at offset XXX on vol YYY

2015-11-20T22:12:47.194Z cpu13:33467)ScsiDeviceIO: 2645: Cmd(0x439dd0d7c400) 0x89, CmdSN 0x2f3dd6 from world 3937473 to dev "naa.50002ac0049412fa" failed H:0x0 D:0x2 P:0x0 Valid sense data: 0xe 0x1d 0x0.

Interestingly, not only HPE is affected by this. Multiple vendors have the same issue. VMware described this issue in KB2113956. HPE has published a customer advisory about this.

Workaround

If you have trouble and you can update, you can use this workaround. Disable ATS heartbeat for VMFS5 datastores. VMFS3 datastores are not affected by this issue. To disable ATS heartbeat, you can use this PowerCLI one-liner:

HPE 3PAR OS updates that fix VMware VAAI ATS Heartbeat issue

5 (100%) 7 votes

Data Protector: Copy sessions to encrypted devices fail after update to 9.07

Leave a reply

Recently, a customer has informed me, that copy sessions to encrypted devices failed, after he has made an update to Data Protector 9.07. The copy sessions failed with this error:

|Critical| From: BMA@<hostname> "" Time: <Date><Time>
|90:6111| Error retrieving encryption key.

1 2	\|Critical\| From: BMA@<hostname> "" Time: <Date><Time> \|90:6111\| Error retrieving encryption key.

The customer uses tape encryption. The destination for the backups is a HPE StoreOnce, and a post-backup copy creates a copy of the data on tape. Backup to disk was running fine, but the copy to tape failed immediately.

The customer has opened a ticket at the HPE support and got instantly a hotfix to resolve this issue. HPE has documented this error in QCCR2A69192. If you run into the same issue, please request hotfix QCCR2A69802. This hotfix consolidates QCCR2A69192 and QCCR2A69318 (The BMA ends abnormally during backup/copy to tape).

Data Protector: Copy sessions to encrypted devices fail after update to 9.07

4.67 (93.33%) 6 votes

Redundancy on the first hop – VRRP

Leave a reply

The Virtual Router Redundancy Protocol (VRRP) was developed in 1998 as an open standard protocol. VRRP is the result of an Internet Engineering Task Force (IETF), and it’s described in RFC 5798 (VRRPv3). VRRP was designed as an open standard protocol, but it uses some patents from Cisco. Its function is comparable to Cisco Hot Standby Router Protocol (HSRP), or to the Common Address Redundancy Protocol (CARP). VRRP solves a very specific problem at the network edge: It offers highly available virtual router interfaces, or in simple words: A highly available default gateway. Its home is the network edge, and because of this, VRRP is a so called first hop redundancy protocol. When moving towards network core, VRRP loses importance. If you move from the network edge to the core, redundancy is primarily offered by dynamic routing protocols and redundant links.

Redundancy on the first hop – VRRP

5 (100%) 10 votes

Get-MailboxDatabase doesn’t show last backup timestamp

Leave a reply

Sometimes you have to check when the last backup of an Exchange mailbox database was taken. This is pretty simple, because the timestamps of the last full, incremental and differential backup is stored for each mailbox database. You can check these attributes using the Exchange Control Panel (ECP), or you can use the Get-MailboxDatabase cmdlet.

Backup successful, but no timestamp?

Take a look at this output. As you can see, there’s no timestamp for the last full, incremental and differential backup. But this database was successfully backuped some minutes before.

[PS] C:\Windows\system32>get-mailboxdatabase | select name, *backup*


Name                           : DB01
BackupInProgress               :
SnapshotLastFullBackup         :
SnapshotLastIncrementalBackup  :
SnapshotLastDifferentialBackup :
SnapshotLastCopyBackup         :
LastFullBackup                 :
LastIncrementalBackup          :
LastDifferentialBackup         :
LastCopyBackup                 :
RetainDeletedItemsUntilBackup  : False

[PS] C:\Windows\system32>get-mailboxdatabase | select name, *backup*

Name : DB01

BackupInProgress :

SnapshotLastFullBackup :

SnapshotLastIncrementalBackup :

SnapshotLastDifferentialBackup :

SnapshotLastCopyBackup :

LastFullBackup :

LastIncrementalBackup :

LastDifferentialBackup :

LastCopyBackup :

RetainDeletedItemsUntilBackup : False

Missing -status switch

Get-MailboxDatabase doesn’t show last backup timestamp

3.67 (73.33%) 9 votes

Disable Outlook cached mode for shared mailboxes

Leave a reply

When you use Microsoft Outlook in cached mode, what I always recommend, and you add additional mailboxes to your outlook profile, you will notice that the OST file will grow. Outlook will download the mailbox items (mails, calendar entries, contacts etc.), and store them in the OST file. This is the default behaviour since Microsoft Outlook 2010. If you want to disable this behaviour, you have two options:

Edit the registry
Use a group policy object (GPO)

Edit the Windows registry

The easiest way is to use a reg file. Copy this text into a file and save it as disablecachedmode.reg. Then double click the file and confirm, that you want to import the registry file.

Disable Outlook cached mode for shared mailboxes

4.88 (97.5%) 8 votes

Changes to supported .NET Frameworks for Exchange 2013/2016

Leave a reply

EDIT: If you have already installed .NET 4.6.1, check this blog post on how to remove it (You Had Me At EHLO…)

Microsoft Exchange heavily relies on Microsoft .NET Framework. Because of this, Microsoft provides a matrix for the supported Microsoft .NET Frameworks. Mostly unknown is the fact, that Exchange doesn’t support the every Microsoft .NET Framework, and this is causing trouble sometimes. Some admins simply install the latest .NET releases because “it doesn’t hurt”. Well… it hurts!

Changes for .NET Framework 4.6.1

Microsoft has changed the support policy for .NET Framework 4.6.1 with the release of Exchange 2013 CU13 and Exchange 2016 CU2. Up to this versions, only .NET Framework 4.5.2 is supported. Starting with Exchange 2013 CU13 and Exchange 2016 CU2, Microsoft supports .NET Framework 4.6.1 together with a hotfix rollup (KB3146715 for Server 2012 R2, KB3146714 for Server 2012 and KB3146716 for Server 2008 R2). If you wish to install .NET Framework 4.6.1, make sure to install Exchange 2013 CU13 or 2016 CU2 first.

Changes to supported .NET Frameworks for Exchange 2013/2016

5 (100%) 8 votes

Receive Connector role not selectable in Exchange 2016 CU2

Leave a reply

Another bug in Exchange 2016 CU2. The Role of a new receive connector is greyed out. You can select “Front-End-Transport”. This is a screenshot from a german Exchange 2016 CU2.

Solution

Use the Exchange Management Shell to create a new receive connector. Afterwards, you can modify it with the Exchange Control Panel (ECP).

[PS] C:\Windows\system32>New-Receiveconnector -Name "Client Frontend Dummy" -RemoteIPRange ("192.168.200.99") -TransportRo
le "FrontendTransport" -Bindings ("0.0.0.0:25") -usage "Custom" -Server "exchange1"

Identity                                Bindings                                Enabled
--------                                --------                                -------
EXCHANGE1\Client Frontend Dummy         {0.0.0.0:25}                            True

[PS] C:\Windows\system32>New-Receiveconnector -Name "Client Frontend Dummy" -RemoteIPRange ("192.168.200.99") -TransportRo

le "FrontendTransport" -Bindings ("0.0.0.0:25") -usage "Custom" -Server "exchange1"

Identity Bindings Enabled

-------- -------- -------

EXCHANGE1\Client Frontend Dummy {0.0.0.0:25} True

Microsoft has confirmed, that this is a bug in Exchange 2016 CU2.

Receive Connector role not selectable in Exchange 2016 CU2

5 (100%) 15 votes

Exchange 2013 Offline Address Book visible after Exchange 2016 deployment?!

Leave a reply

After deploying a new Microsoft Exchange organization with Exchange 2016, or after deploying a Microsoft Exchange 2016 into an existing organization, you might notice a strange behaviour regarding the Offline Address Books (OAB).

[PS] C:\Windows\system32>Get-OfflineAddressBook

Name                                    Versions                                AddressLists
----                                    --------                                ------------
Standard-Offlineadressliste             {Version2, Version3, Version4}          {\Globale Standardadressliste}
Standard-Offlineadressliste (Ex2013)    {Version4}                              {\Globale Standardadressliste}

[PS] C:\Windows\system32>Get-OfflineAddressBook

Name Versions AddressLists

---- -------- ------------

Standard-Offlineadressliste {Version2, Version3, Version4} {\Globale Standardadressliste}

Standard-Offlineadressliste (Ex2013) {Version4} {\Globale Standardadressliste}

Huh?! Where does this Exchange 2013 OAB come from? As you can see in the cmdlet output, there’s no Exchange 2013 in this organization.

[PS] C:\Windows\system32>Get-ExchangeServer | select Name, AdminDisplayVersion

Name                                                 AdminDisplayVersion
----                                                 -------------------
MAIL-1                                               Version 14.3 (Build 123.4)
MAIL-2                                               Version 15.1 (Build 466.34)
MAIL-3                                               Version 15.1 (Build 466.34)

[PS] C:\Windows\system32>Get-ExchangeServer | select Name, AdminDisplayVersion

Name AdminDisplayVersion

---- -------------------

MAIL-1 Version 14.3 (Build 123.4)

MAIL-2 Version 15.1 (Build 466.34)

MAIL-3 Version 15.1 (Build 466.34)

There is no Exchange 2013 server in this organization. Only Exchange 2010 (Build 14.3) and 2016 (Build 15.1).

Exchange 2013 Offline Address Book visible after Exchange 2016 deployment?!

5 (100%) 6 votes

vcloudnine.de

… virtualization on cloud 9

I’m routing on the edge…

Related Posts:

Routed Port vs. Switch Virtual Interface (SVI)

Related Posts:

HPE 3PAR OS updates that fix VMware VAAI ATS Heartbeat issue

Related Posts:

Data Protector: Copy sessions to encrypted devices fail after update to 9.07

Related Posts:

Redundancy on the first hop – VRRP

Related Posts:

Get-MailboxDatabase doesn’t show last backup timestamp

Related Posts:

Disable Outlook cached mode for shared mailboxes

Related Posts:

Changes to supported .NET Frameworks for Exchange 2013/2016

Related Posts:

Receive Connector role not selectable in Exchange 2016 CU2

Related Posts:

Exchange 2013 Offline Address Book visible after Exchange 2016 deployment?!

Related Posts: