From c9c208933bd13f097f3c7c9a7eccbe33e668a72b Mon Sep 17 00:00:00 2001 From: Oguz Bektas Date: Thu, 23 Apr 2020 13:47:13 +0200 Subject: [PATCH] pmgcm: typos, grammar and rephrasing fixups Signed-off-by: Oguz Bektas Reviewed-By: Aaron Lauterer --- pmgcm.adoc | 45 ++++++++++++++++++++++----------------------- 1 file changed, 22 insertions(+), 23 deletions(-) diff --git a/pmgcm.adoc b/pmgcm.adoc index 76bfcd3..ec850f7 100644 --- a/pmgcm.adoc +++ b/pmgcm.adoc @@ -30,7 +30,7 @@ failures in email systems are just not acceptable. To meet these requirements we developed the Proxmox HA (High Availability) Cluster. The {pmg} HA Cluster consists of a master and several slave nodes -(minimum one node). Configuration is done on the master. Configuration +(minimum one slave node). Configuration is done on the master. Configuration and data is synchronized to all cluster nodes over a VPN tunnel. This provides the following advantages: @@ -43,8 +43,8 @@ provides the following advantages: * high performance We use a unique application level clustering scheme, which provides -extremely good performance. Special considerations where taken to make -management as easy as possible. Complete Cluster setup is done within +extremely good performance. Special considerations were taken to make +management as easy as possible. A complete cluster setup is done within minutes, and nodes automatically reintegrate after temporary failures without any operator interaction. @@ -64,7 +64,7 @@ The HA Cluster can also run in virtualized environments. Subscriptions ------------- -Each host in a cluster has its own subscription. If you want support +Each node in a cluster has its own subscription. If you want support for a cluster, each cluster node needs to have a valid subscription. All nodes must have the same subscription level. @@ -79,7 +79,7 @@ second node is used as quarantine host, and only provides the web interface to the user quarantine. The normal mail delivery process looks up DNS Mail Exchange (`MX`) -records to determine the destination host. A `MX` record tells the +records to determine the destination host. An `MX` record tells the sending system where to deliver mail for a certain domain. It is also possible to have several `MX` records for a single domain, they can have different priorities. For example, our `MX` record looks like that: @@ -94,7 +94,7 @@ proxmox.com. 22879 IN MX 10 mail.proxmox.com. mail.proxmox.com. 22879 IN A 213.129.239.114 ---- -Please notice that there is one single `MX` record for the Domain +Notice that there is a single `MX` record for the domain `proxmox.com`, pointing to `mail.proxmox.com`. The `dig` command automatically puts out the corresponding address record if it exists. In our case it points to `213.129.239.114`. The priority of @@ -124,28 +124,28 @@ server (mail.provider.tld) if the primary server (mail.proxmox.com) is not available. NOTE: Any reasonable mail server retries mail delivery if the target -server is not available, i.e. {pmg} stores mail and retries delivery -for up to one week. So you will not lose mail if your mail server is +server is not available, and {pmg} stores mail and retries delivery +for up to one week. So you will not lose mails if your mail server is down, even if you run a single server setup. Load balancing with `MX` records ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -Using your ISPs mail server is not always a good idea, because many +Using your ISP's mail server is not always a good idea, because many ISPs do not use advanced spam prevention techniques, or do not filter -SPAM at all. It is often better to run a second server yourself to +spam at all. It is often better to run a second server yourself to avoid lower spam detection rates. -Anyways, it’s quite simple to set up a high performance load balanced -mail cluster using `MX` records. You just need to define two `MX` records +It’s quite simple to set up a high performance load balanced +mail cluster using `MX` records. You need to define two `MX` records with the same priority. Here is a complete example to make it clearer. First, you need to have at least 2 working {pmg} servers (mail1.example.com and mail2.example.com) configured as cluster (see section xref:pmg_cluster_administration[Cluster administration] below), each having its own IP address. Let us assume the following -addresses (DNS address records): +DNS address records: ---- mail1.example.com. 22879 IN A 1.2.3.4 @@ -154,7 +154,7 @@ mail2.example.com. 22879 IN A 1.2.3.5 It is always a good idea to add reverse lookup entries (PTR records) for those hosts. Many email systems nowadays reject mails -from hosts without valid PTR records. Then you need to define your `MX` +from hosts without valid PTR records. Then you need to define your `MX` records: ---- @@ -162,9 +162,8 @@ example.com. 22879 IN MX 10 mail1.example.com. example.com. 22879 IN MX 10 mail2.example.com. ---- -This is all you need. You will receive mails on both hosts, more or -less load-balanced using round-robin scheduling. If one host fails the -other one is used. +This is all you need. You will receive mails on both hosts, load-balanced using +round-robin scheduling. If one host fails the other one is used. Other ways @@ -173,7 +172,7 @@ Other ways Multiple address records ^^^^^^^^^^^^^^^^^^^^^^^^ -Using several DNS `MX` records is sometimes clumsy if you have many +Using several DNS `MX` records is sometimes tedious if you have many domains. It is also possible to use one `MX` record per domain, but multiple address records: @@ -195,9 +194,9 @@ using DNAT. See your firewall manual for more details. Cluster administration ---------------------- -Cluster administration can be done on the GUI or using the command +Cluster administration can be done in the GUI or by using the command line utility `pmgcm`. The CLI tool is a bit more verbose, so we suggest -to use that if you run into problems. +to use that if you run into any problems. NOTE: Always setup the IP configuration before adding a node to the cluster. IP address, network mask, gateway address and hostname can’t @@ -243,8 +242,8 @@ Adding Cluster Nodes [thumbnail="pmg-gui-cluster-join.png", big=1] -When you add a new node to a cluster (using `join`) all data on that node is -destroyed. The whole database is initialized with cluster data from +When you add a new node to a cluster (using `join`), all data on that node is +destroyed. The whole database is initialized with the cluster data from the master. * make sure you have the right IP configuration @@ -257,7 +256,7 @@ pmgcm join You need to enter the root password of the master host when asked for a password. When joining a cluster using the GUI, you also need to -enter the 'fingerprint' of the master node. You get that information +enter the 'fingerprint' of the master node. You can get that information by pressing the `Add` button on the master node. CAUTION: Node initialization deletes all existing databases, stops and